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73
estimating the relationship between improved transpor-
tation and industrial location decisions distinguishing be-
tween those transportation decisions that create new
economic development and those that merely redistribute
economic activity, prioritizing the development of major
highway corridors by focusing on potential economic de-
velopment, estimating the economic impacts of road
weight restrictions on rural communities, relating trans-
portation investments to the job market (jobs created
directly and indirectly), estimating the portion of total
cost related to transportation in various economic sectors,
and assessing the economic consequences of severe met-
ropolitan congestion examining the erects of policies and
regulations, estimating intermodal relationships, devel-
oping pricing and revenue strategies.
AREA 3: OPERATIONS AND
CONTROL
Project 3-1 FY '63 and FY '64
Development of Criteria for Evaluating Traffic
Operations
Cornell Aeronautical Laboratory
Jaime F. Torres
Feb. 15, 1963 July 2, 1964
Feb. 29, 1964 Feb. 28, 1966
$78,965 $79,913
Research Agency:
Principal Invest.:
Elective Date:
Completion Date:
Funds:
This research project provided an investigation into the
application of criteria based on travel time, driver com-
fort, safety, and vehicle running costs. The linear com-
bination of these factors weighted by an appropriate set
of cost coefficients quantified the operational performance.
A procedure was studied which would provide estimates
of the four components based on measurements of traffic
volume and an inventory of roadway characteristics.
Travel time, volume, and roadway inventory data were
collected from several cities and analyzed. Estimating
relationships were derived for many classes of urban ar-
terials, whereby travel time can be obtained from the
measurement of volume and a knowledge of the street
characteristics. A survey vehicle was equipped to monitor
skin resistance, heart pulse, and respiration of two subjects
in traffic while steering, brake, throttle, and speed were
being recorded to study driver comfort. Accident data in
the Buffalo area were analyzed and related to the safety
factor, and vehicle running costs were estimated through
the use of speed distributions for a sample of streets.
The final report was not published in the NCHRP
report series; however, microfiche of the report may be
purchased (see final page of this section for ordering in-
formation).
Project 3-2 FY '63 and FY '64
Surveillance Methods and Ways and Means of
Communicating with Drivers
Research Agency: Cornell Aeronautical Laboratory
Principal Invest.: Morton I. Weinberg
Elective Date: February 15, 1963
Completion Date: April 30, 1966
Funds: $246,756
This project was concerned with the development, prac-
tice, and evaluation of various methods of surveillance
and means of communicating with drivers.
The report of the first phase of research described a
predictive model to provide warning of impending conges-
tion, study of a ramp advisory signal, and use of an
airborne observer for traffic control. It has been published
as: NCHRP Report 9, "Traffic Surveillance and Means
of Communicating with Drivers."
In the second phase of the project, the researchers
developed the mathematical logic to predict the effects
from unexpected blockages on a freeway and validated
the model on the John C. Lodge Freeway in Detroit. Also
included was an evaluation of an airborne surveillance
and control system. The results of this phase have been
published as: NCHRP Report 28, "Surveillance Methods
and Ways and Means of Communicating with Drivers."
In the third phase of the project, a computer-controlled
signal system for a typical urban complex was synthesized,
including control logic and equipment requirements. The
results of this phase have been published as: NCHRP
Report 29, "Digital-Computer-Controlled Traffic Signal
System for a Small City."
Project 3-3 FY '63 and FY '64
Sensing and Communication Between
Vehicles
Research Agency:
Principal Invest.:
Elective Date:
Completion Date:
Funds:
The Ohio State University
Dr. Thomas H. Rockwell
Dr. Joseph Treiterer
February 15, 1963
November 30, 1965
$163,190
This project involved establishment of the operating
requirements of a communication system designed to en-
able better communications between vehicles on express-
way-type facilities. The final report has been published
as: NCHRP Report 51, "Sensing and Communication
Between Vehicles."
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Project 3-4 FY '63, FY '64, and FY '66
Means of Locating Disabled or Stopped Ve-
hicles and Methods of Communication
with a Central Location
Research Agency:
Principal Invest.:
Effective Date:
Completion Date:
Funds:
Airborne Instruments Laboratory
Fred Pogust
March 1, 1963 July 1, 1965
March 31, 1965 Dec. 15, 1966
$78,517 $49,474
This study was directed toward evaluating the nature
and extent of the problem and describing the need for
communication as well as the benefits of locating disabled
vehicles. An additional task was researching the ways
that information about disabled or stopped vehicles may
be used.
An interim report has been published as: NCHRP Re-
port 6, "Means of Locating and Communicating with
Disabled Vehicles."
Following the comprehensive review of the nature, ex-
tent, and characteristics of the stopped-vehicle problem
conducted during the first year of research, the researchers
continued to investigate the feasibility of a detector sys-
tem. A roadside vehicle detector system was developed
using a silicon photo-voltair diode as the roadside re-
ceiving unit, and signalling was performed by a vehicle-
mounted relay-type interrupting device which modulates
infrared-emitting diodes. A prototype system was built,
tested, and demonstrated to the project panel.
The final report has been published as: NCHRP Report
40, "Means of Locating Disabled or Stopped Vehicles."
Project 3-5 FY ,63, FY '64, FY ,66, and FY ,69
Improved Criteria for Designing anc! Timing
Traffic Signal Systems
Research Agency: Planning Research Corp.
Principal Invest.: F. A. Wagner, Jr.
Elective Date: 3/1/63 7/1/66 8/1 /68
Completion Date: 12/31/65 7/31/67 12/31/69
Funds: $123,030 $48,155 $93,717
The over-all objective of the research was to determine
the most efficient method of timing traffic signals for
isolated intersections, arterial highways, and grid net-
works of city streets. The research was accomplished in
three phases.
The results of the first phase of research, involving
methods of signal timing for the isolated intersection, have
been published as: NCHRP Report 3, "Improved Criteria
for Traffic Signals at Individual Intersections-Interim
Report," and NCHRP Report 32, "Improved Criteria for
Traffic Signals at Individual Intersections."
The second phase involved development and compre-
hensive, closely controlled, scientific testing of several
advanced concepts for operating tra~c-signal systems on
urban arterial streets. The results indicate that a signifi
cant degree of improvement in traffic operation is possible
through application of advanced control methods. This
phase final report has been published as: NCHRP Report
73, "Improved Criteria for Designing and Timing Traffic
Signal Systems Urban Arterials."
The objective of the third phase was to simulate and
field test promising signal-control logic that will produce
improved signal timings for a grid network of traffic sig-
nals. The final report has been published as: NCHRP
Report 124, "Improved Criteria for Traffic Signal Systems
in Urban Networks."
Project 3-6 FY '63, FY '64, and FY ,66
Effect of Regulatory Devices on Intersectional
Capacity and Operation
Research Agency:
Principal Invest.:
Effective Date:
Completion Date:
Funds:
De Leuw, Cather & Company
Ronald Prefer
April 1, 1963
August 15, 1966
$153,175
The purpose of this research was to identify the effect
of specified traffic regulatory devices on intersection ca-
pacity and operations and on systems of traffic facilities.
The effects of stop and yield signs were investigated as
they apply to capacity, traffic operations, safety, driver
acceptance, and the traffic operations of the area of
influence.
The initial phase of research has been published as:
NCHRP Report 11, "Effect of Control Devices on Traffic
Operation." The report examines efficient methods of in-
tersection study and derives some preliminary relation-
ships concerning the operations of intersections with
YIELD and two-way STOP control and their street system
effects.
During the second phase of research, field data were
collected at STOP- and -sign locations in the areas
of Chicago, San Francisco, New York, and Toronto.
Analyses were made to select criteria for intersection con-
trols and develop a method for applying them. Programs
and procedures were developed to integrate and analyze
the field data collected during the first phase. Detailed
traffic-control-devices questionnaires were analyzed from
States, cities, and counties throughout the country.
The final report has been published as: NCHRP Report
41, "Erect of Control Devices on Traffic Operations."
Project 3-7 FY '64, '65, '67, '71, and '73
Establishment of Standards for Highway
Noise Levels
Research Agency: Bolt Beranek and Newman
Principal Invest.: Andrew Kugler
Effective Date: 2/1/64 10/14/68 4/1/71
Completion Date:
Funds:
9/1/72
4/30/67 1/15/70 6/30/72 11/30/74
$144,920 $69,930 $49,927 $307,486
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75
This project was concerned with the evaluation of noise
levels of the various classes of highways and the effec-
tiveness of controlling highway noise through highway
design features as well as the reduction of noise produc-
tion by means of legislation and vehicle regulation. Ques-
tions relating to highway noise levels and their erect on
adjacent land users frequently arise in urban highway
planning and design.
The Phase I research involved the selection of the most
appropriate means and units for measuring and evaluating
highway noise. Its results have been published as:
NCHRP Report 78, "Highway Noise-Measurement, Sim-
ulation, and Mixed Reactions."
The Phase II research objective was to prepare a high-
way design noise manual for the practicing highway en-
gineer. In addition, a magnetic tape recording was
produced to demonstrate basic elements of highway noise
and to present examples illustrating changes in traffic
noise. Loan copies of the tape recording are available on
request to the TRB Audio-Visual Library (see final page
of this section for ordering information). The results of
the Phase II research have been published as: NCHRP
Report 117, "Highway Noise- A Design Guide for High-
way Engineers."
The objective of the Phase III research was to conduct
a thorough measurement program on various noise re-
duction treatments under a variety of traffic and envi-
ronmental conditions. This research developed a tie
between field data and analytic approaches so that the
perfo~ance of noise reduction treatments may be more
accurately predicted. The results of the Phase III research
have been published as: NCHRP Report 144, "Highway
Noise A Field Evaluation of Traffic Noise Reduction
Measures."
The Phase IV research started with the following ob-
jectives: to summarize the present state-of-the-art for con-
trolling the noise-producing properties of the individual
mechanical components of motor vehicles that lead to
the composite noise produced by motor vehicles on high-
ways; to assess the technological and economic feasibility
of reduction of traffic noise that will enable highway of-
ficials to seek federal and local legislation that might
redistribute the burden of noise control; and to improve
procedures for highway noise control that will allow the
designer to more realistically assess the highway noise
problem.
The research has been completed. Final report mate-
rials include a computer program for use with the design
guide and a 17-min color film entitled "Quiet Highway
Design." The film is available on a loan basis from the
TRB Audio-Visual Library (see final page of this section
for ordering information), and copies of the computer
program can be supplied upon written request to the
NCHRP. The final report on the concluding phase of this
research has been published in two volumes: NCHRP
Report 173, "Highway Noise Generation and Control,"
and NCHRP Report 174, "Highway Noise A Design
Guide for Prediction and Control."
A report on a study task on time-varying highway noise
criteria was not published, but microfiche of the report
may be purchased (see final page of this section for
ordering information).
Project 3-8 FY '64 and FY '65
Factors influencing Safety at Highway-Rai!
Grade Crossings
Research Agency:
Principal Invest.:
Effective Date:
Completion Date:
Funds:
Alan M. Voorhees & Associates
David W. Schoppert
Dan W. Hoyt
Dec. 1, 1963 Apr. 1, 1965
Dec. 31, 1964 Jan. 6, 1967
$17,171 $74,250
This study was directed toward the interpretation and
analysis of currently available highway-rail grade-crossing
data in the United States.
The initial research reviewed previous work in this area
and developed a mathematical model for predicting ac-
cidents, and this was tested with accident data obtained
from Minnesota, Oregon, and Virginia. A warrant was
developed based on the cost of providing protective
devices and the cost of possible accident savings.
Later work involved the development and testing of
improved grade-crossing protective devices, and several
experimental devices were studied by the agency. A hu-
man factors study was completed. Several important
sources of data were found that facilitated the research
associated with the development of the accident predictive
model as well as refinement of the proposed criteria for
grade-crossing protection. Data acquired from Stanford
University included 18 years of data at 617 crossings, and
data acquired from the Ohio Department of Highways
included all accidents occurring at 1,000 rural grade cross-
ings. From the Interstate Commerce Commission, the
investigators obtained more than 15,000 grade-crossing
accident reports spanning a five-year period.
The project report has been published as: NCHRP
Report 50, "Factors Influencing Safety at Highway Rail
Grade Crossings."
Project 3-9 FY '66
Analysis and Projection of Research on Traffic
Surveillance, Communication, and Con-
tro!
Research Agency:
Principal Invest.:
Elective Date:
Completion Date:
Funds:
Roy Jorgensen and Associates
Karl Moskowitz
October 15, 1966
January 14, 1968
$23,760
The purpose of this study was to review the results of
NCHRP Projects 3-2, 3-3, and 3-4, together with the
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76
accomplishments of other recently completed research in
this area in the United States and abroad, and to deter-
mine the state of the art and set forth guidelines regarding
the proposed future research efforts to be conducted in
this area.
The project report has been published as: NCHRP
Report 84, "Analysis and Projection of Research on
Traffic Surveillance, Communication, and Control."
Project 3-10 FY '66
Application of Vehicle Operating Character-
istics to Geometric Design and Traffic Op
erations
Research Agency: Cornell Aeronautical Laboratory
Principal Invest.: Morton I. Weinberg
Dr. Kenneth J. Tharp
January 1, 1966
March 10, 1967
$41,520
Elective Date:
Completion Date:
Funds:
This research was directed at identifying the motor
vehicle characteristics that are related to highway geo-
metric design and traffic control operations. The objective
was to determine the relationships between the vehicle
and its operating environment. Vehicle characteristics
were reviewed; where appropriate, highway design criteria
were suggested.
Elements of geometric design and traffic operations
presented in the basic design and policy manuals were
analyzed to determine how vehicle characteristics are
being utilized. A rational approach was made to deter-
mine, expand, or modify the existing criteria. The results
of the review revealed those vehicle characteristics which
should be known and used in designing and operating
streets and highways. For vehicle characteristics which
are presently unknown or where information is outdated,
methods of obtaining data and methods of using this
information in geometric design and traffic operations
were recommended.
The final report has been published as: NCHRP Report
68, "Application of Vehicle Operating Characteristics to
Geometric Design and Traffic Conditions."
Project 3-11 FY '67
Optimizing Street Operations Through Traffic
Regulations and Control
Research Agency:
Principal Invest.:
Elective Date:
Completion Date:
Funds:
Peat, Marwick, Mitchell & Co.
James H. Kell
September 1, 1966
September 30, 1968
$258,331
This research was directed to applying the best traffic
regulation and control techniques to an area of typical
urban streets and evaluating results. Innovations that may
be expected to improve operational efficiency were ex-
plored. The cities of Sunnyvale and Redwood, Calif., were
selected as the cooperating demonstration test cities. The
research emphasis was placed on a quantified evaluation
of the erect of traffic regulation and control techniques
on the central business districts of these cities.
As this research study included the significant areas of
business performance and public opinion, greater insight
was gained into the political feasibility of a proposed
traffic change. The study findings substantiated the theory
that no major traffic improvement plan can be imple-
mented, regardless of the extent to which it may serve
the public interest, unless it meets with the support of
the general public, especially that of the business com-
munity.
The final report has been published as: NCHRP Report
110, "Optimizing Street Operations Through Traffic Reg-
ulations and Control."
Project 3-12 FY '67, FY '68, and FY '71
Development of Information Requirements
and Transmission Techniques for High-
way Users
Research Agency:
Principal Invest.:
Effective Date:
Completion Date:
Funds:
Airborne Instruments Laboratory
M.A. G.F. G.F.
Warskow King King
10/1/66 3/29/71 4/1/68
12/31/67 12/1/69 12/11/72
$198,655 $100,500 $99,821
The objective of the over-all research problem was the
development of a well-defined information system for the
highway user. The system represents all conditions with
which the driver is routinely, occasionally, and rarely
confronted.
Analysis of the driving task disclosed that the opera-
tions performed by a driver can be characterized in terms
of a hierarchy. It was found that a demanding priority
(primacy) exists in satisfying information needs, and it
was concluded that satisfying the primary of information
needs is basic to the design of a highway information
system. A procedure was developed for the systematic
application of these principles to actual highway situa-
tions in accordance with basic information system re-
quirements. In addition, current sign use was investigated,
particularly the night legibility problem, to determine
problem areas in sign application criteria. Mathematical
analyses were presented on the probability of sign block-
age by trucks and the effect of lateral displacement of
signs. A sign design procedure to incorporate the findings
with regard to sign use was outlined. The test site for the
project was located in North Carolina.
The first- and second-phase research has been com-
pleted, and the project report has been published as:
NCHRP Report 123, "Information Requirements and
Transmission Techniques for Highway Users."
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77
Although engineers have certain established concepts
and standards regarding highway guide signing, addi-
tional research, identified as Phase III of this project, was
conducted to determine whether or not these present stan-
dards provide the information required to guide motorists
properly on their journeys. This research involved critical
highway signing in and around urban areas and included
inner-city signing, beltway signing, and junction signing
for arterial routes and freeways.
The final report was not published in the NCHRP
report series; however, microfiche of the report may be
purchase (see final page of this section for ordering
information).
Project 3-13 FY '68
Guidelines for Medial and Marginal Access
Control of Major Roadways
Research Agency:
Principal Invest.:
Elective Date:
Completion Date:
Funds:
Texas A & M University
Research Foundation
Dr. Vergil G. Stover
September 1, 1967
November 30, 1969
$149,293
A need existed for guides in selecting the degree of
access control for a specific project and for selecting the
type, location, and width of median and median openings
and the design and frequency of entrances to be associated
with the degree of access control.
Factors considered in this research were: accident fre-
quency and severity; cost of physical construction and
right-of-way to accomplish access control; legal consid-
erations; traffic patterns; service to the highway user; mo-
tor vehicle operating costs; travel time and costs; land
use; convenience of access to abutting property; property
values; and provision for future needs for access control
and for changing traffic characteristics, user requirements,
or land use.
The project report has been published as: NCHRP
Report 93, "Guidelines for Medial and Marginal Access
Control on Major Roadways."
Project 3-14 FY '68
Optimizing Flow on Existing Street Networks
Research Agency:
Principal Invest.:
Elective Date:
Completion Date:
Funds:
Edwards & Kelcey
Walter E. Pontier
October 1, 1967
January 10, 1970
$990,000
This project investigated the benefits to traffic flow in
downtown areas which can be achieved by application of
traffic engineering measures. Experimentation to quantify
the effect of road improvements was carried on in two
study areas the downtown portions of Louisville, Ky.,
and Newark, N.J. Data developed for control and analysis
of these experiments were subjected to statistical evalu-
ation to describe those controlling conditions which in-
fluence measurements in the downtown area and to
develop meaningful relationships which describe the qual-
ity of traffic flow, attaining a level of service definition
for downtown streets. Methods were developed for ap-
plication of the results of this research to streets of other
areas.
The final report has been published as: NCHRP Report
1 13, "Optimizing Flow on Existing Street Networks." As
part of the project, a film, "Relief for Tired Streets," was
produced. It demonstrates the results that can be obtained
by applying sound traffic engineering practices to our
nation's urban traffic problems. Loan copies of the film
may be obtained through the TRB Audio-Visual Library.
Project 3-15 FY '70
Weaving Area Operations Study
Research Agency: Polytechnic Institute of New York
Principal Invest.: Dr. Louis J. Pignataro
Elective Date: October 1, 1969
Completion Date: December 31, 1973
Funds: $300,000
The objective of this research was to analyze and eval-
uate the procedures recommended in Chapters 7 and 8
of the 1965 Highway Capacity Manual. Based on the
findings the agency is to develop improved techniques for
the analysis and design of weaving sections.
A new algorithm has been developed and evaluated,
using both field data and an available data base from
FHWA sources. The design and analysis procedures have
been developed in such a way that graphical, analytical,
and computer solutions can be employed. These tech-
niques have been reviewed and tested by selected State
highway agencies.
The research has been completed, and the final report
has been published as: NCHRP Report 159, "Weaving
Areas Design and Analysis."
Project 3-16 FY '70
Freeway Lane Drops
Research Agency:
Principal Invest.:
Effective Date:
Completion Date:
Funds:
System Development Corp.
Antranig V. Gafarian
Diane N. Goodwin
Nov. 1, 1969 May 1, 1972
Apr. 30, 1971 Oct. 31, 1973
$99,789 $76,815
Many variables affect the operating conditions and
safety of the various lane drop configurations. Sound cri-
teria for the selection of the proper lane drop design for
the objectives of Phase I were:
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78
1. From field data, determine the effectiveness of ex-
isting mainline lane drops from the standpoint of safety
and traffic operations.
2. Determine the effects of the significant parameters
associated with various levels of safety and traffic service.
3. Recommend configurations for lane drops based on
the findings of objectives 1 and 2. In this context "con-
figurations" includes distance from the nearest upstream
and downstream ramps.
In the first phase, three lane-drop sites with different
geometric configurations were studied intensively to de-
termine traffic operations and safety effects. The report
on this initial phase was not published; however, mi-
crofiche of the report may be purchased (see final page
of this section for ordering information).
The Phase II research continued with the same three
objectives and the added objective of recommending re-
medial treatments in a set of guidelines based on analysis
of descriptive data and traffic performance from many
existing lane-drop sites.
The research has been completed, and the final report
has been published as: NCHRP Report 175, "Freeway
Lane Drops."
Project 3-17 FY '71
Improving Traffic Operations and Safety at
Exit Gore Areas
Research Agency:
Principal Invest.:
Elective Date:
Completion Date:
Funds:
The Pennsylvania State University
James I. Taylor
January 1, 1971
November 30, 1972
$79,983
This research project addressed the problem of erratic
maneuvers, such as backing up and stopping in the gore
area, that occur with alarming frequency at freeway exit
areas. Specifically, it was directed toward answering three
basic questions: What factors cause motorists to make
erratic maneuvers at exit gore areas? What remedial de-
vices can be employed to reduce their occurrence at ex-
isting sites? And, what changes in design and traffic
control criteria can be recommended that will minimize
the problem at future sites? The results of this study
provide answers to these questions, and the findings can
be used by traffic and design engineers to enhance the
safety and traffic operations at freeway exit facilities.
The final report has been published as: NCHRP Report
145, "Improving Traffic Operational and Safety at Exit
Gore Areas." A 10-min color film, "Safety at Freeway
Exits," highlighting the research findings is also available
on a loan basis from the TRB Audio-Visual Library (see
final page of this section for ordering information).
Project 3-18~1) FY '70
Improved Control Logic for Use with Com-
puter-Controlled Traffic
Research Agency:
Principal Invest.:
Stanford Research Institute
Dr. Dale W. Ross
Dr. Thomas L. Humphrey
Elective Date: July 15, 1971 April 15, 1975
Completion Date: May 15, 1974 June 30, 1977
Funds: $323,998 $57,662
The objective of this research was to study traffic flow
and control interaction and to develop an advance control
concept, strategy, and computer program. The research
has included development of an operational control pro-
gram that has the capability of calculating optimal offset
patterns for a network of signalized intersections and
determining independent and variable signal split adjust-
ments. The program, designed for application under all
levels of network traffic volumes, including oversaturated
conditions, has been tested and evaluated with actual
traffic in the San Jose traffic control system.
A final report describing the research and the resulting
ASCOT program package will not be published in the
NCHRP report series, but copies are available on either
a loan or purchase basis. A 20-min color film describing
the program and its functions is also available on a loan
basis for the cost of mailing and handling. The film,
"Improved Control Logic for Use with Computer-Con-
trolled Traffic," is available on a loan basis from: TRB
Audio-Visual Library; the report may be purchased for
$10.00 (see final page of this section for ordering infor-
mation).
Project 3-18(2) FY ,71
Traffic Control in Oversaturated Street Net
works
Research Agency: Polytechnic Institute of New York
Principal Invest.: Dr. Louis J. Pignataro
Effective Date: September 1, 1971
Completion Date: June 30, 1975
Funds: $200,000
The specific objectives of the first phase of the project
were to:
1. Define the measures of network oversaturation and
determine the existing scope and magnitude of the
oversaturated street-network problem.
2. Define the root causes of the problem.
3. Evaluate the relative effectiveness of existing oper-
ations and control techniques used to combat the problem.
4. Prepare detailed operational guidelines for appli-
cation of existing traffic operations and control techniques
of illustrated effectiveness.
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79
5. Describe alternative concepts of advanced traffic-
control techniques for improving the efficiency of traffic
operation in oversaturated networks.
6. Formulate a detailed plan and program for system-
atic development, testing, and application of improved
traffic control in oversaturated networks.
A final report on this phase will not be published;
unedited draft copies are available on loan upon request
to the NCHRP Program Director. The essential findings
of this report have been published as NCHRP Research
Results Digest 51.
A continuation phase with the following objectives was
initiated: to carry out further studies in minimal-response
signal policies, nonsignal effects and remedies, and highly
responsive policies and to produce a set of recommen-
dations and guidelines for applying solutions to the prob-
lems of oversaturation. The research has been completed,
and the final report covering the entire project has been
published as: NCHRP Report 194, "Traffic Control in
Oversaturated Street Networks."
Project 3-18(3) FY ,75
Cost-Effectiveness Methodology for Evalua-
tion of Signalized Street Network Sur-
veittance and Control Systems
Research Agency:
Principal Invest.:
Elective Date:
Completion Date:
Funds:
JHK & Associates
Thomas L. Stout
May 1, 1975
April 15, 1977
$123,267
The objectives of this research were to develop and to
demonstrate a practical total-system cost-effectiveness
methodology for the comparative evaluation of alternative
traffic surveillance and control systems for signalized
street networks. The methodology developed should take
into consideration all pertinent factors bearing on the
choice of the best control technique, including such fac-
tors as types of hardware components used; extent of real-
time human operator interface required or desired; degree
of automated traffic sensing employed for either on-line
control or offline system support purposes; physical and
traffic flow characteristics of the street network being
controlled; and technical skills and other resources of the
operating agency.
The project's revised final report and a separate manual
have been submitted. The research report, "Signal System
Evaluation Methodology," will not be published in the
NCHRP report series but is available on a loan basis.
The manual, "An Approach for Selecting Traffic Control
Systems" may be obtained on a loan basis or purchased
for $11.00 (see final page of this section for ordering
information).
Project 3-18(4) FY '76
Methodology for Performance Evaluation of
Signalized Network Control Strategies
Research Agency:
Principal Invest.:
Elective Date:
Completion Date:
Funds:
Computran Systems Corporation
Dr. H. Nathan Yagoda
July 21, 1977
November 20, 1980
$148,705
The objective of this research was to develop and dem-
onstrate a practical methodology for the comparative
performance evaluation of alternative traffic control strat-
egies for signalized street networks. The research ad-
dressed networks of ten or more signalized intersections.
The research has been completed, and copies of the
agency report are available on a loan basis or microfiche
of the report may be purchased (see final page of this
section for ordering information).
Project 3-19 FY '72
Grade Effects on Traffic Flow Stability and
Capacity
Research Agency: Midwest Research Institute
Principal Invest.: Andrew D. St. John
Elective Date: September 1, 1971
Completion Date: August 31, 1974
Funds: $220,443
The objectives of this research were to:
1. Determine and verify methods for calculating the
acceleration and speed-maintenance capabilities on grades
of a wide range of motor-vehicle types, including trucks
and combinations, buses, campers, house/railers, low-per-
formance passenger cars, and other atypical vehicles nor-
mally found on Interstate and primary highway systems.
2. Determine the factors that create instabilities in the
traffic stream on grades. Particular attention is to be given
to the role of low-performance and unusual-size vehicles
in the creation of these instabilities.
3. Determine, through use of appropriate digital-com-
puter traffic-simulation models and by correlated field
measurements, the passenger-car equivalencies for the
vehicle types enumerated in objective 1.
4. Determine the effects on safety and traffic flow with
both restricted and unrestricted operations of 12- and 14-
ft-wide loads on highways in varying terrain. The goal of
this objective is to provide guidance for the regulation of
these unusual load widths.
5. Estimate, by use of correlations between traffic flow
characteristics and accident frequencies, the accident im-
plications for the situations studied in objectives 2 and 4.
The research has been completed, and the final report
has been published as: NCHRP Report 185, "Grade Ef-
fects on Traffic Flow Stability and Capacity."
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80
Project 3-20 FY '73
Traffic Signal Warrants
Research Agency: KLD Associates
Principal Invest.: Edward B. Lieberman
Elective Date:
Completion Date:
Funds:
Sept. 1, 1972 Nov. 1, 1974
Apr. 15, 1974 Dec. 31, 1976
$120,000 $81,935
The objective of this research was to evaluate the ad-
equacy of existing warrants, or the need for revised or
additional warrants, in meeting current needs for deter-
mining whether a traffic signal should be installed.
The research has been completed, and the final report
has been submitted. New warrants have been developed
and are presented in the report, which also includes rec-
ommended changes for the relevant text of the Manual
on Uniform Traffic Control Devices dealing with traffic
signal warrants. Procedures for field validation of the
proposed warrants have also been designed and are rec-
ommended in the report.
The report has been provided to the National Advisory
Committee on Uniform Traffic Control Devices for con-
sideration. The report was not published in the NCHRP
report series; however, microfiche of the report may be
purchased (see final page of this section for ordering
information).
Project 3-20A FY '80
Peak-Hour Traffic Signal Warrants
Research Agency:
Principal Invest.:
Elective Date:
Completion Date:
Funds:
JHK & Associates
R. David Henry
Jay H. L. Calhoun
June 23, 1980
July 31, 1982
$150,000
The objective of this research was to evaluate and verify
the peak-hour warrant suggested by the Signals Subcom-
mittee of the National Advisory Committee on Uniform
Traffic Control Devices (NAC) and the peak-hour war-
rant developed as part of NCHRP Project 3-20. A rec-
ommendation with supporting documentation and
justification was desired for adoption of a warrant, in-
cluding either modifications to the above warrants or
consideration of an alternative warrant.
Field studies were conducted at 190 intersections to
obtain the necessary data to analyze each warrant ele-
ment. Intersection delay, percent stops, traffic volume,
and queue length were determined. The field studies in-
cluded six urban areas and various intersection types.
A new peak-hour warrant was developed based on
queue length. In general, a signal is considered to be
warranted when there is an average queue of at least four
vehicles for one hour on a typical day.
The project report has been published as: NCHRP
Report 249, "Peak-Hour Traffic Signal Warrant."
Project 3-21 FY '74
Motorist Response to Highway Guide Signing
Research Agency:
Principal Invest.:
Effective Date:
Completion Date:
Funds:
BioTechnology, Inc.
Fred R. Hanscom
Wallace G. Berger
April 1, 1974
January 31, 1976
$272,071
The first research phase under this project was directed
toward identification of promising measures of driver re-
sponse to guide signing and to development and validation
of such measures. The research has been completed, and
copies of the agency report are available on a loan basis
upon written request to the NCHRP or microfiche of the
report may be purchased (see final page of this section
for ordering information).
The second research phase, NCHRP Project 3-21~2),
extends the Phase I effort to address a specific application;
i.e., use of changeable-message signs in advance of freeway
lane closures.
Project 3-21(2) FY '77
Effectiveness of Changeable-Message Dis-
plays in Advance of High-Speed Freeway
Lane Closures
Research Agency:
Principal Invest.:
Effective Date:
Completion Date:
Funds:
BioTechnology, Inc.
Fred R. Hanscom
December 1, 1979
August 31, 1981
$170,993
NCHRP Project 3-21, "Motorist Response to Highway
Guide Signing," developed various driver response mea-
sures that can be used to determine the effectiveness of
different signs. Project 3-21~2) extended the original re-
search by applying the response measures to a specific
signing problem.
The objective of this research was to determine effective
advance message displays (e.g., words, symbols, and lane
signals) for lane closures on high-speed freeways. This
research provides, as a result of field studies at selected
lane-closure sites, an objective analysis of traffic perfor-
mance in response to various changeable-message dis-
plays.
Volume I of the agency's report, containing the major
findings from Project 3-21~2), has been published as
NCHRP Report 235, "Effectiveness of Changeable Mes-
sage Displays in Advance of High-Speed Freeway Lane
Closures." Volume II of the agency's report, providing
greater detail on the field study and questionnaire results,
is available from NCHRP for $3.50 prepaid. Microfiche
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81
of the report is also available (see final page of this section
for ordering information).
Project 3-23 FY '74
Guidelines for Uniformity in Traffic Control
Signal Design Configurations
Research Agency: KLD Associates
Project 3-22 FY '74 Principal Invest.: Gerhart F. King
Guiclelines for Design and Operation of Ramp Effective Date: April 8, 1974
Control Systems Completion Date: July 28, 1977
Funds: $308,779
Research Agency:
Principal Invest.:
Elective Date:
Completion Date:
Funds:
Stanford Research Institute
Dale P. Masher
Aprill5, 1974
December31,1975
$199,030
The objectives of this project were to analyze existing
ramp control techniques and to develop design procedures
for freeway ramp control systems. The research consid-
ered those types of ramp control designed to keep free-
ways operating at or near capacity during peak periods
with a minimum of manual operation. Merge control,
gap-acceptance systems, and computerized control of
traffic signals on surface streets in the freeway corridor
may be relevant tools, but the development of design
guidelines for these techniques was considered to be out-
side the scope of this project. Additionally, this project
did not address guidelines for extensive freeway surveil-
lance features except where these features relate to the
control systems.
The final report will not be published in the regular
NCHRP series; however, microfiche of the draft report,
"Guidelines for Design and Operation of Ramp Control
Systems," December 1975, may be purchased (see final
page of this section for ordering information).
Project 3-22A FY '77
Guidelines for Design and Operation of Ramp
Control Systems
Research Agency:
Principal Invest.:
Elective Date:
Completion Date:
Funds:
Texas A & M University
Research Foundation
Charles W. Blumentritt
February 1, 1977
March 31, 1981
$249,538
Preliminary guidelines were developed in NCHRP
Project 3-22 for designing and operating ramp control
systems. The objective of NCHRP Project 3-22A was to
extend this research to provide more specific guidelines
to evaluate the cost effectiveness of alternative ramp con-
trol system designs. The three levels of control investi-
gated were local pretimed, traffic responsive, and
systemwide.
The final report, including the guidelines, has been
published as: NCHRP Report 232, "Guidelines for Se-
lection of Ramp Control Systems."
The purpose of this study was the preparation of guide-
lines for optimum traffic control signal design configu-
rations at intersections and mid-block crossing locations.
The research included the following objectives:
1. Preparation of an annotated bibliography of relevant
literature and research in progress pertaining to traffic
control signal design configurations.
2. With reference to Part IV, Sections B and D, and
Part VII, Section D, of the 1971 MUTCD, a study of
traffic control signal design configurations, including, but
not limited to: number and arrangement of lenses in signal
faces, size of signal lenses, type of signal lenses (arrows
and program visibility signal), visibility and shielding of
signal faces, number of signal faces, horizontal and ver-
tical location of signal faces.
3. Identification and consideration of all factors related
to the approach to signalized locations that affect or in-
fluence the observance, safety, and efficiency of traffic
control signals.
4. Development and validation of a detailed set of
traffic control signal design guidelines based on field,
human behavioral, and theoretical analyses that would
produce optimum traffic control signal design configu-
rations.
5. Preparation of proposed revisions of the referenced
sections of the 1971 MUTCD.
6. Identification of the areas in which further research
is indicated.
The final report was not published in the NCHRP
report series; however, microfiche of the report may be
purchased (see final page of this section for ordering in-
formation).
Project 3-24 FY '75
Determine the Luminous Requirements for
Retroreftective Highway Signing
Research Agency: University of Michigan
Principal Invest.: Dr. Paul L. Olson
Elective Date: September 1, 1974
Completion Date: April 30, 1977
Funds: $100,000
The purpose of this study was to define the relationship
between sign luminance and legibility in a way that would
assist in selecting optimum material choices for various
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82
signing applications as well as aid in decisions concerning
maintenance and replacement.
A laboratory study was carried out to define the erects
of luminance, contrast, color, and driver visual charac-
teristics on legibility distance. A computer model was
developed to predict the legibility distance of a sign based
on the laboratory data as well as geometric and photo-
metric variables. A field study was conducted in which
legibility distance predicted by the model was compared
with legibility distance measured on a numbr of real and
simulated signs. Data were developed that show graphi-
cally the relationship between legibility distance and the
photometric properties of background and legend mate-
rials.
The final report was not published in the NCHRP
report series; however, a copy of it, entitled "Determine
the Luminous Requirements of Retroreflective Highway
Signing," is available at a cost of $7.00 (see final page of
this section for ordering information).
Project 3-25 FY '76
Cost and Safety Effectiveness of Highway
Design Elements
Research Agency:
Principal Invest.:
Elective Date:
Completion Date:
Funds:
Roy Jorgensen Associates, Inc.
Joseph F. Banks, Jr.
Dr. Richard L. Beatty
Dr. David B. Brown
July 15, 1975
April 16, 1978
$260,576
The objectives of this research were (1) to identify the
key geometric characteristics and combinations of char-
acteristics of road and street designs that affect accident
frequency and severity; (2) to quantify the effects of vary-
ing the key characteristics and combinations of charac-
teristics on accident frequency and severity; and (3) to
develop a methodology that can be used by engineers in
measuring the cost-effectiveness of the various levels of
each design element.
About 50 design features were found to have some
relationship to safety. Because only a limited number of
design elements could be studied in depth during this
research, the features of pavement width, shoulder width,
and shoulder surface type for rural two-lane highways
were selected for quantifying their relationship to accident
and frequency and severity.
A safety cost-effectiveness methodology was developed
to incorporate the quantified relationships into a practical
design procedure. Utilization of the safety relationships
and methodology contained in the final report will provide
an optimum design for pavement width, shoulder width,
and shoulder type. The methodology does not contain a
rigid procedure for selection of the final design, but pro-
vides the necessary cost-effectiveness information for the
designer to make an objective decision. The final design
selected must also consider traffic and vehicle operating
characteristics, which may override the design based on
safety cost-effectiveness. However, by applying the meth-
odology, the safety ramifications of all alternatives can
be determined.
Research has been completed, and the final report has
been published as: NCHRP Report 197, "Cost and Safety
Effectiveness of Highway Design Elements."
Project 3-26 FY '77
Investigation of Selected Noise Barrier
Acoustical Parameters
Research Agency:
Principal Invest.:
Elective Date:
Completion Date:
Funds:
The Pennsylvania State University
Dr. Sabih I. Hayek
Dr. James M. Lawther
December 1, 1976
February 28, 1980
$224,494
The basic project objective was to complete an analysis
of cross-section shape, surface characteristics, and the
influence on ground-cover effects. The significance of
these parameters was evaluated theoretically in terms of
the sensitivity of barrier effectiveness to each, and the
bounds of their effects were delineated in the first phase
of the project.
The second phase of the project emphasized scale-
model experimentation designed to verify the findings of
the first phase. The tests included evaluation of insertion
loss models applied to the different barrier configurations
and study of the ground-effects problem and propagation
characteristics related to a pavement adjoined by an
impedance-covered terrain.
The agency's final report, results of the scale-model
experiments, is available on a loan basis upon written
request to the NCHRP or a microfiche copy may be
purchased (see final page of this section for ordering in-
formation).
Project 3-27 FY '77
Guidelines for Selecting Traffic Control at
Indiviclua! Intersections
Research Agency:
Principal Invest.:
Effective Date:
Completion Date:
Funds:
Alan M. Voorhees & Associates,
Inc.
Philip J. Tarnoff
November 15, 1976
July 31, 1979
$150,000
The objective of this research was to develop guidelines
for selecting the most appropriate type of traffic signal
control for an individual intersection in both urban and
rural areas. Pretimed, semi-traffic-actuated, and full-
traffic-actuated control types were evaluated. An anno-
tated bibliography of previous studies was prepared, and
current practices were reviewed in depth with local traffic
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83
engineering agencies. Numerous factors affecting the
choice of control type were identified.
A cost-e~ectiveness evaluation methodology was de-
veloped to assist in the selection of traffic signal control
and addresses such items as (a) initial costs, (b) mainte-
nance costs, (c) over-all delay, (d) percentage of traffic
stopped, (e) vehicle emissions, (f) fuel consumption, and
(g) other direct and indirect user costs. The incremental
benefits of more sophisticated levels of control and op-
erational reliability are fully considered. Cost and oper-
ational data are also included in the cost-e~ectiveness
methodology to reduce the data collection requirements
of future users. Adjacent intersections are addressed in
the guidelines in regard to the selection of coordinated
versus independent operations.
Research has been completed, and the findings have
been published as: NCHRP Report 233, "Selecting Traffic
Signal Control at Individual Intersections."
Project 3-28 FY '78
Development of an improved Highway
Capacity Manual
Research Agency:
Principal Invest.:
Effective Date:
Completion Date:
Funds:
JHK & Associates
William R. Reilly
December 15, 1977
August 15, 1979
$161,000
Project 3-28 is a multiphase effort with the overall
objective of providing the basis for a revision of the High-
way Capacity Manual (HCM). Phase I (Project 3-28) had
the threefold objective of (1) determining the current and
future needs of users of the HCM, (2) assembling existing
information for dissemination as an interim document
prior to revision of the entire Manual, and (3) identifying
gaps in the available techniques that require additional
research to develop new information for inclusion in the
revised Manual.
The second phase of this research includes two projects
that have been initiated to satisfy the high-priority re-
search needs identified in Phase I. Phase II research in-
cludes NCHRP Projects 3-28A and 3-28~2~. The final
phase will be directed to assembly of information from
work sponsored by NCHRP, FFIWA, and others into a
form for publication as a revised Manual.
Research on Phase I has been completed. The final
report presents the results of an extensive survey of user
needs and a summary of related research. In addition, 15
areas of needed research are identified. Copies of the
agency's report are available on a loan basis (see final
page of this section for ordering information).
Interim materials were assembled and developed in
Phase I for immediate distribution, as well as for eventual
inclusion in the revised Manual. The Transportation Re-
search Board has published the interim materials as TRB
Circular 212 which includes capacity analysis techniques
for transit, pedestrians, and unsignalized intersections.
Project 3-28A FY '80
Two-Lane, Two-Way Rural Highway Capacity
Research Agency:
Principal Invest.:
Effective Date:
Completion Date:
Funds:
Texas A & M Research Foundation
Dr. Carroll J. Messer
May 1, 1980
February 28, 1983
$157,492
NCHRP has initiated a multiphase research effort with
the objective of providing the basis for a revised, improved
Highway Capacity Manual (HCM). Phase I research
(Project 3-28) identified the specific needs of users of the
HCM, provided interim materials for dissemination prior
to development of the revised Manual, and identified ad-
ditional research projects that should be conducted to
provide input to the revised Manual. Project 3-28A was
part of the Phase II effort, which was directed to satisfying
the highest priority research needs identified in Phase I.
The procedures contained in the 1965 HCM for analysis
of traffic operations on two-lane, two-way rural highways
are based on the fundamental traffic flow relationships
that expressed operating speed as a function of vehicular
volume and capacity for various prevailing conditions.
Users of the HCM procedures indicated a need for im-
provement in several elements of the technical analysis.
The objective of this research was to develop an ana-
lytical procedure to evaluate the capacity and level of
service for two-lane, two-way rural roads in an appro-
priate form for inclusion in a revised HCM.
Existing simulation models were reviewed with a de-
tailed analysis of the simulation parameters, such as truck
speeds, grades, directional volumes, headways, and speed
distributions. The MRI simulation model was selected for
use in this research.
Field studies were conducted at selected sites in Texas,
Pennsylvania, Colorado, West Virginia, and Alberta, Can-
ada, to collect speed, volume, and related data for use in
the analytical framework. These field data, combined with
prior calibration data and other reported rural highway
data, were used to indicate the general level of accuracy
for the MRI model.
Relationships between traffic volume, levels of service,
and related parameters were determined using the field
data and the simulation model. These relationships were
structured into an integrated procedure for calculation of
directional speed (and other appropriate measures of ef-
fectiveness), volume, capacity, and level of service for a
wide range of traffic and highway design conditions. A
step-by-step analysis procedure was prepared.
TTI's final report includes a draft chapter for the HCM
that will be finalized under Project 3-28B. Therefore, the
report will not be published in the regular NCHRP series,
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87
road, (2) proximate land use, (3) potential use by emer-
gency vehicles, (4) potential environmental impact, (5)
energy consumption, (6) maintenance, (7) liability, and
(8) societal implications.
3. Identify sources and methods of obtaining data nec-
essary to support the application of factors. The types of
data include: (1) accident data, (2) inventory data, (3)
cost information, (4) liability issues, (5) maintenance
agreements, and (6) operational and mobility considera-
tions, especially passenger trains, buses, and hazardous
materials vehicles.
4. Develop a framework of procedures utilizing the
factors identified in Task 2 to assist in selecting one of
the four alternatives described above. Detailed analysis
guidelines and a recommended format for presenting the
evaluation results are included.
5. The framework of procedures developed in Task 4
were applied to two case studies.
6. Prepare a final research report that documents the
rationale used to select the framework and that describes
its application. Prepare a separate user's guide, including
examples, on the use of the framework.
Research has been completed and the final report and
user's guide have been published in the regular NCHRP
report series as NCHRP Report 288.
Project 3-32 FY '85
Temporary Pavement Markings for Work
Zones
Funds:
Research Agency: Texas A & M Research Foundation
Principal Invest.: Dr. Conrad L. Dudek
Effective Date: May 1, 1985
Completion Date: February 28, 1987
$164,990
Temporary traffic control has become a larger per-
centage of the costs on many construction, maintenance,
or utility projects. With the prospects of continued infla-
tion, limited resources, and high interest rates, it is im-
perative that all aspects of temporary traffic control be
evaluated for economy in application and benefits to the
public.
FHWA has issued guidelines and proposed changes
in the Manual on Uniform Traffic Control Devices
(MUTCD) regarding Temporary Markings for Construc-
tion and Maintenance Areas. The proposed changes
would require as a minimum 4-ft broken lines as tem-
porary markings on most projects, which is more than
double what many states now specify. If adopted as the
national standard, 4-ft markings would increase project
costs.
Research was needed to determine if the proposed 4-
ft markings would actually result in significant safety and
operational improvements in comparison to current prac-
tice.
The specific objective of this research was to compare
the safety and operational electiveness of Oft, 2-ft, and
4-ft temporary broken line pavement markings in work
zones. The scope and test conditions studied were: (1)
surfacing operation on a two-lane, two-way facility; (2)
data collection during hours of darkness; (3) dry roadway
conditions; (4) tangent and curve sections; (5) use of the
test states typical pavement marking cycle (40 to 50 ft);
and (6) field tests in real or staged work zones that are
open to tragic. In order to meet this objective, the fol-
lowing tasks were performed:
Task 1. A critical review of the literature on safety
and operational effects of pavement marking in work
zones was conducted
Task 2. A detailed data collection and analysis plan
along with a proposed schedule was developed. The plan
included (1) experimental design and analysis plan, in-
cluding the rationale for selecting the recommended ap-
proach and proposed sample sizes; (2) measures of
effectiveness (MOE's) to be used to evaluate the three
different stripe lengths; and (3) methods and location of
field measurements.
Task 3. Data collection and analysis at six sites were
performed.
Task 4 A research report including a discussion of the
traffic engineering and human factors implications of the
research findings to current practice and to the proposed
change was prepared.
All research has been completed, and the final report
has been provided to the National Committee on Uniform
Traffic Control Devices and to FHWA. On the basis of
the limited conditions studied and the project findings,
further research is deemed necessary before any further
changes in the MUTCD are contemplated.
The findings of this research project were presented by
the principal investigator at the TRB Annual Meeting in
January, 1988. A paper, "Field Studies of Temporary
Pavement Markings at Overlay Project Work Zones on
Two-Lane, Two-Way Rural Highways," by Conrad L.
Dudek, R. Dale Huchingson, F. Thomas Creasey, and
Olga Pendleton, has been published in Transportation
Research Record 1160, Traffic Control Devices 1988. The
Record also includes a discussion by Anita W. Ward and
an author's closure. A decision on publication of the final
report is pending. Loan copies are available from
NCHRP.
Project 3-33 FY ,85
Capacity and Level-of-Service Procedures for
Multilane Rural and Suburban Highways
Research Agency:
Principal Invest.:
Effective Date:
Completion Date:
Funds:
JHK & Associates
William R. Reilly
June 1, 1985
May31,1989
$475,132
Chapter 7, "Multilane Highways," of the new Highway
Capacity Manual (HCM) published in 1985, is predicated
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88
largely on the limited research used for the 1965 edition
and on extrapolation from recent studies of other highway
types, especially freeways. In the absence of an adequate
data base concerning the operating and capacity char-
acteristics of the multilane highway, research is needed
to develop this information and to prepare an improved
chapter on multilane highways.
The objective of this research was to confirm and/or
develop operational, design, and planning procedures for
determining the capacity and levels of service of multilane
highways, both rural and suburban. This research will:
(1) review the current state of the art, (2) develop an
adequate data base and, (3) validate, revise, or develop
new analytic procedures. Items to be considered include
separation of traffic directions, access characteristics,
roadside development, presence of signalized and unsig-
nalized intersections, lane widths, lateral obstructions,
geometries, and other variables that may impede smooth
traffic flow. The proposed procedures will replace Chapter
70fthel985HCM.
The major thrust of this effort was focused on multilane
highway facilities having four or more lanes. The research,
however, also considered special multilane configurations
such as three-lane, two-way operation (2-1 split) and the
provision of a continuous left-turn lane. New material
developed for these special configurations will be incor-
porated into the appropriate HCM chapter.
To accomplish this objective the following tasks was
performed in two phases:
Phase I:
Task 1. Conduct a review of the pertinent literature
and current research.
Task 2. Evaluate the adequacy of the current state-of-
the-art procedures used in analyzing multilane highway
capacity and level of service.
Task 3. Prepare preliminary capacity analysis proce-
dures to serve as the basis for a data collection plan. The
proposed capacity analysis method may be a refinement
or revision of the existing procedures or may require an
entirely new concept of multilane capacity analysis.
Task 4. Prepare a field data collection plan to quantify
the traffic flow relationships.
Task 5. Prepare a Phase I report, including the pro-
posed data collection plan and a revised, detailed budget
for Phase II.
Phase II:
Task 6. Collect field data according to the approved
plan.
Task 7. Reduce and analyze the data collected under
Task 6 to obtain values for the appropriate traffic flow
relationships.
Task 8. Prepare a report describing the proposed final
form and content of the capacity and level-of-service anal-
ysis procedures.
Task 9. Write a new version of Chapter 7, "Multilane
Highways," containing the new analysis procedures.
All tasks have been completed and the final report has
been drafted. The study recommendations and a draft
Chapter 7 will be provided to the Highway Capacity
Committee for review and a decision on inclusion in the
Highway Capacity Manual. The Capacity Committee is
expected to act on the recommendations at their January
1989 meeting.
Project 3-34 FY '86
The Feasibility of a National Heavy-Vehicle
Monitoring System
Research Agency: Arthur D. Little, Inc.
Principal Invest.: Ashok B. Boghani
Elective Date: November 1, 1985
Completion Date: September 30, 1988
Funds: $499,79 1
Various types of information on heavy vehicles are
collected by federal, state, and local governments to sup-
port highway planning and design activities, as well as to
carry out weight enforcement programs and tax admin-
istration. Collecting and processing this information is
extremely costly from the viewpoint of both government
and private industry, and in many cases the data are not
as complete or as accurate as desired for the intended
purpose. In addition to actual dollar costs, the present
system suffers from burdensome paperwork, operator in-
convenience and potential hazard, lack of enforcement
uniformity, and inconsistency among the individual
states. International inconsistency is also a concern. The
potential use of the collected information for other pur-
poses (e.g., by private industry in fleet and operations
management, and by enforcement agencies in locating
stolen equipment) has also not been fully explored.
New technologies in automatic vehicle identification
(AVI), automatic vehicle classification (AVC), and weigh-
in-motion (WIM) are considered to potentially offer a
more cost-effective approach to the collection of heavy-
vehicle data. The interest in AVI systems, integrated with
AVC and/or WIM, is so great that a group of western
states and Canadian provinces is embarking on a multi-
jurisdictional project to demonstrate the utility of an in-
tegrated electronic heavy-vehicle monitoring system. This
project, called the Crescent Demonstration Project, is
limited in scope and is not designed to address all of the
questions and problems involved in the implementation
of a multijurisdictional, national or international system.
Therefore, there is a need to evaluate the feasibility of
applying these relatively new technologies at the national
and/or regional levels and to build on the existing knowl-
edge from the Crescent Project and other related studies.
Institutional issues such as privacy, access to competitive
information, and potential for manipulation and evasion
of the system will be major determinants of feasibility
and acceptability. These issues will therefore play a prom-
inent part in the evaluation.
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89
The objective of this research was to identify and eval-
uate the needs, issues, requirements, and feasibility of
using an automated system (AVI/AVC/WIM) as a cost-
effective, statistically sound replacement and/or supple-
ment to existing heavy-vehicle data collection systems.
This research will encompass: (1) the identification of
different system-design configurations for the integration
of AVI, AVC, and WIM to provide appropriate levels of
monitoring and related confidence levels; (2) amount of
equipment/automation to achieve different objectives; (3)
site location criteria on a state, regional, and nationwide
scale; (4) an economic analysis of the alternative levels
of monitoring; and (5) the full range of issues associated
with implementation and operation.
The following tasks will be completed:
Task 1 Identify the types and range of existing and
potential national, state, and private industry functions
(activities) that are or could be supported by heavy-vehicle
data.
Task 2 Determine the required deployment density
of an automated data collection system to provide an
acceptable statistically based level of accuracy for each
function.
On the basis of the identified deployment requirements,
group functions with similar needs that can be satisfied
with a common system configuration of deployment den-
sity and level of sophistication (i.e., number of sites,
number of vehicles equipped, type of data collection
equipment, national/regional area, etc.~. Approximately
3 to 5 configurations are anticipated to cover the range
of functions, data requirements, and needed levels of
accuracy.
Task 3 Examine each system configuration against
the issues and related considerations identified in Task 1.
Task 4 Submit an interim report presenting the find-
ings of Tasks 1 through 3.
Task 5 Conduct a cost-benefit analysis for each ap-
proved system configuration (including the incremental
cost/benefit associated with each function). The advan-
tages and/or disadvantages of automated systems will be
compared to existing data collection and processing sys-
tems; and the impact on other data collection, processing,
and reporting procedures that would be affected by the
use of an automated system will be identified.
Task 6 Describe implementation considerations for
each recommended system configuration. These consid-
erations will include the technical, operational, institu-
tional, cost, financial, and legislative issues, the data base
management system requirements, and any other consid-
erations identified during the course of the research.
Task 7 Prepare a final report.
Research has been completed and the final report will
be published as: NCHRP Report 303, "Feasibility of a
National Heavy Vehicle Monitoring System."
Project 3-35 FY '86
Speed-Change Lanes
Research Agency: JHK & Associates
Principal Invest.: William R. Reilly
Elective Date: June 1, 1986
Completion Date: March 30, 1989
Funds: $250,000
Changing vehicle and driver population characteristics
makes it necessary to periodically reexamine highway
design criteria. The speed-change lane is one of the most
common highway features because it can be either a per-
manent feature (terminals, lane drops, etc.) or a tempo-
rary feature (construction and maintenance zones).
The more diverse vehicle population on the highways
today, ranging from light low-powered automobiles to
heavy trucks, makes a reexamination of speed-change lane
criteria necessary to keep design parameters current.
The objective of this research is to examine the current
design parameters which establish speed-change lane
length. Based on a review of current practice, updated
vehicle performance characteristics, and new driver-be-
havioral data, recommended design procedures will be
developed for specific applications taking into account the
type of facility, geometries, and other relevant consider-
ations. This research will address existing and new ac-
celeration and deceleration lanes on freeways. The scope
of this research does not include (a) the design of weaving
sections, (b) work zone applications, (c) ramp metering,
and (d) new accident studies.
To accomplish this objective, the following tasks will
be conducted:
Task 1 Review literature and operational experience
through a limited survey of state highway officials.
Task 2- Update vehicle mix and performance data.
Using available data to the maximum extent possible,
update the vehicle parameters used in speed-change lane
criteria. Gaps in the published data will be filled by con-
tacting manufacturers and others and, if necessary, by
conducting limited operational tests. Changes in vehicle
mix and selection of a new design vehicles will be con-
sidered.
Task 3 Determine behavioral characteristics of the
driver/vehicle unit in speed-change lanes. Conduct driver
information or task analyses to identify the driving tasks
required to negotiate a speed-change lane. If necessary
conduct laboratory, closed field, or field studies to verify
the analyses or to fill gaps in available data.
Task 4-Develop a conceptual framework for design
of freeway speed-change lanes. This framework will in-
clude revised or new design criteria applicable to specific
conditions (e.g., facility type, grade, curvature, terminals,
volume).
Task 5 Develop a plan to field test the proposed
design criteria.
Task 6 Conduct field test studies.
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Task 7 Analyze the field study data to confirm the
design criteria developed in Task 4
Task 8 Develop application procedures. A range of
typical projects and conditions will be described including
reconstruction and new construction. Guidance on ex-
treme applications (e.g., steep grades, high truck volumes)
will also be provided.
Task 9 Prepare a draft final report. One appendix to
the report will be a stand-alone design guide tailored to
state/local designers.
Tasks 1 through 7 have been completed and work is
nearing completion on the user application procedures
and the final report. Panel review and revision of all
materials will require a time extension until about March
of 1989.
Project 3-36 FY '87
Development of a Low-Cost Bridge Weigh-In-
Motion System
Research Agency:
Principal Invest.:
Elective Date:
Completion Date:
Funds:
Bridge Weighing Systems, Inc.
Richard E. Snyder
February 16, 1987
August 16, 1989
$400,000
Truck weight, dimension, and speed data are required
for a wide variety of purposes, including maintenance
management programs, pavement and bridge manage-
ment systems, pavement and bridge design, cost allocation
studies, and for compliance with FHWA-mandated ve-
hicle weight and speed monitoring programs. Current
methods for collecting these data are very costly to both
the states and the trucking industry and are often inef-
fective. A technique is needed to economically acquire
information on the characteristics of heavy vehicles and
to provide a data base that can be used for improved
planning, design, and maintenance of highways and
bridges.
At present, most truck weight data are obtained from
conventional o~-road weigh stations at fixed locations on
major highways. However, there are well known disad-
vantages associated with the operation of these facilities:
they occupy valuable real estate, require expensive equip-
ment, and need costly operating personnel. The stations
often become over-used, increasing delays to trucking
firms. Further, these stations are often easily evaded by
overloaded vehicles or by those who wish to avoid delays.
A number of states have been investigating bridge weigh-
in-motion (WIM) systems, but the cost of equipment and
manpower has prevented widespread implementation.
There is a need to develop a low-cost system, suitable
for widespread application, that can combine load mea-
surement with vehicle classification. One approach to this
problem is the further development of current bridge
weigh-in-motion technology, using low-cost, low-power
electronics and transducers.
The objective of this research is to develop a low-cost
bridge weigh-in-motion (WIM) system capable of pro-
viding the traffic data used in the design and maintenance
of highways and bridges. This system will be able to record
gross vehicle weights and classify vehicles, at a minimum,
and also be able to record individual axle weights within
the limits of the specific bridge and site characteristics.
Further, the system will use state-of-the-art technology,
have a target purchase price of $5,000 to $10,000 per
unit, have a low life-cycle cost, be capable of interfacing
with automatic vehicle identification (AVI) equipment,
and be deployable on both bridges and large culverts.
This research will include the development, testing, and
demonstration of a "turnkey" prototype system.
The research will include the following tasks:
Task 1 Review existing bridge WIM/AVC systems
including the technical design, practical considerations,
costs, hardware and software requirements, operational
and maintenance problems, reliability, and accuracy. This
review will also consider other technology that may be
transferable to components of a WIM/AVC system.
Task 2 Develop a conceptual system design defining
the data requirements, equipment performance criteria,
hardware and software requirements, and estimated pur-
chase price. At a minimum, the system will be able to
collect the following data:
· Gross vehicle weight for vehicles over 12,000 pounds.
. Number of axles and spacing.
. Traffic counts of all vehicles.
· Speed.
· Vehicle classification.
In addition to these minimum requirements, individual
axle weights are also desired if the system can obtain this
information with reasonable accuracy.
Task 3 Develop an operational model for laboratory
testing. This model will include the necessary software
for data recording and transmission, the signal processing
algorithms, the interface between the WIM and AVC
hardware, and, to the extent possible, the provision for
interfacing with AVI hardware. The model will also in-
clude complete fabrication of the hardware components
for testing and modification under controlled laboratory
conditions.
Task 4- Conduct laboratory tests to evaluate the sys-
tem performance and capabilities.
Task 5 Build prototypes of the WIM/AVC system
for field testing. Special considerations include the differ-
ent types of bridges and culverts on which the system
will be used, environmental factors, installation and main-
tenance requirements, vandal resistance, among others.
Task 6 Field test the prototypes.
Task 7 Evaluate the field test results and modify the
system design and prototypes as necessary.
Task 8 Build a prototype of the final system design
for delivery to the NCHRP, along with complete docu-
mentation to support subsequent manufacture and pro
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curement. This documentation will include detailed
reproducible production drawings, software with a prop-
erly annotated source listing, and installation and oper-
ating instructions. The research product will be in the
public domain for use by states and others in procuring
low-cost bridge WIM equipment.
Task 9-Prepare a final report.
Tasks 1 through 4 have been completed.
Project 3-37 FY So
Capacity of Ramp-Freeway Junctions
Research Agency:
Principal Invest.:
Elective Date:
Completion Date:
Funds:
In developmental stage
(36 months)
$500,000
When the Highway Capacity Manual (HCM) was re
vised in 1985, the required data and understanding for
many traffic situations were found not to exist. For ex
pediency, "reasonable" judgments were made about how
to analyze such situations, but it was understood that
such material was unreliable and was to be revised as
soon as possible. The Transportation Research Board sub
sequently published a prioritized list of subjects about
which the HCM is unreliable and research is needed
(Circular 319~. Number one on that list of priorities is
the capacity of ramp-freeway junctions. A theory which
accounts for the impact of geometric and traffic variables
must be developed and calibrated with a nationwide sur
vey. The objective of this research shall be to: (1) Develop
a theory or algorithm that can calculate the capacity and
level of service of ramp-freeway junctions as functions of
geometric and traffic variables. (2) Calibrate that theory
or algorithm with a nationwide data sample. The geo
metric variables considered should include merge/di
verge angle, length and type of acceleration/deceleration
lane, grades, design speeds, and number of lanes on the
ramp and on the mainline. The traffic variables considered
should include traffic volume on the ramp and on the
mainline, percent trucks, and arrival pattern (random/
ramp-metered/platoon). The research can be divided into
six major tasks: Task 1. Ascertain the state-of-the-art
in ramp-freeway capacity analysis. This task includes a
literature survey but it also includes coordination and
consultation with other, related research. Task 2. Select
80 experimental sites. Experimental sites must cover the
full range of traffic, geometric, and geometric, and geo
graphical variables. Task 3. Formulate a model of the
capacity of ramp-freeway junctions. This model may take noloz~es
form of a theoretical relationship or of an algorithm. The
critical issue is that the model be able to predict the level
of service and capacity of ramp-freeway junctions. Op
erating speed is a desirable, but not essential, measure of
effectiveness. Task 4 Conduct a pilot study at four of the
experimental sites. Calibrate the model. Task 5. Revise
the model and data collection procedures, prepare an
interim report, and confer with the NCHRP Advisory
Panel before embarking on the full data collection. The
purpose of this task is to ensure that both the researchers
and the NCHRP panel understand the state-of-the-art
and agree as to what the most promising model and data
collection methodologies are. Task 6. Perform a full data
collection at 76 experimental sites. Calibrate the revised
model.
Project 3-38~1) FY '87
Assessment of Advanced Technologies for
Relieving Urban Traffic Congestion
Research Agency:
Principal Invest.:
Effective Date:
Completion Date:
Funds:
Castle Rock Consultants, Inc.
Peter Davies
July 1, 1987
June 30, 1989
$199,752
Traffic congestion is rapidly becoming one of the most
serious problems affecting urban areas. Traffic operations
techniques and systems are needed that can substantially
increase capacity and improve traffic flow efficiency.
While it is essential that "best practices," new construc-
tion, and traditional traffic engineering approaches in
dealing with traffic demand be vigorously used, innovative
and advanced technology needs to be incorporated into
the highway system if significant relief for urban traffic
congestion is to be realized at economic and social costs
below the cost of constructing extensive new conventional
facilities.
Application of advanced technologies in areas such as
motorist communication, information and navigation sys-
tems, vehicle guidance, control systems, and others has
the potential for relieving traffic congestion. Issues related
to applying such systems to help alleviate traffic and trans-
portation problems have yet to be fully explored.
The objectives of this research are to: (1) identify and
assess the most promising advanced technologies and sys-
tems that can improve urban highway traffic operations
by achieving significant increases in capacity and traffic
flow; and (2) for the most promising of these technologies
and systems, formulate a plan for research, development,
testing, and demonstration.
The following two research phases are to be accom-
plished:
Phase 1 Preliminary Assessment of Advanced Tech
~ .
-
Task 1 Identify advanced and innovative technologies
and systems that offer significant promise of improving
urban highway traffic operations. These improvements
may include increased capacity, enhanced traffic flow, or
improved system operational efficiency.
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Task 2-Conduct a preliminary quantitative assess-
ment of each technology with respect to costs and benefits.
This assessment will relate~each technology to the type
of urban congestion problems that can be alleviated (e.g.,
freeway incidents, recurring congestion on freeways and
arterials).
Task 3-Conduct a preliminary assessment of the in-
stitutional and organizational issues, public/private sec-
tor roles, funding mechanisms, and potential economic
benefits of widescale use related to the implementation
aspects of these technologies.
Task 4 Prepare an interim report including a list of
the most promising technologies in order of their potential
for reducing congestion and in terms of the chance of
successful implementation.
Phase 2 Detailed Assessment and Program Devel-
opment
Task 5 Perform a detailed assessment of each of the
technologies selected in Task 4. This assessment will in-
clude a more detailed analysis of the factors covered in
Phase 1. In addition, it will examine such issues as en-
vironmental considerations, social impacts, develop-
mental risks, and implementation risks.
Task 6 On the completion of Task 5, prepare and
present an executive level briefing to a limited number of
top highway officials on the results and recommendations
to date. The purpose will be to exchange information and
to obtain input to assist the contractor in formulating
research, development, and demonstration (RD&D) pro-
gram plans.
Task 7 Develop a detailed RD&D program plan for
each technology assessed in Task 5, describing the next
stage of research, planning, and program development.
The research and development element of the plan will
define the specific new research requirements to advance
these technologies to a demonstration stage by the mid-
1990's. The demonstration element of the plan will de-
scribe the scale and application of the demonstrations to
be developed. It will also address commercialization con-
siderations, institutional and organizational issues, pub-
lic/private sector roles, educational needs, and
demonstration risks. RD&D program costs will be esti-
mated for each plan formulated.
Task 8 Prepare and present an executive level briefing
to the same participants who were involved in Task 6.
This briefing should cover the recommended RD&D pro-
gram with emphasis on implementation considerations.
Task 9 Prepare a final report.
Tasks 1 through 4 have been completed and the interim
report was reviewed at a panel meeting in April, 1989.
Subsequently TRB, with the concurrence of AASHTO
and FHWA, has proposed a broader, policy study of the
issues being addressed in project 3-38~1~. Following ini-
tiation of the TRB policy study, to be designated as a
continuation of this project, the research agency will pur
sue the original objectives in a way that will complement
the new TRB policy study. Further details are provided
in the project description immediately following.
Project 3-381A FY '90
A Study to Assess Advanced Vehicle and
Highway Technologies
Research Agency:
Principal Invest.:
Elective Date:
Completion Date:
Funds:
Transportation Research Board
Robert E. Skinner, Jr.
(18 months)
$42,500 (additional funding is ex-
pected to be provided by other
Federal agencies and industry
sponsors).
Traffic congestion is rapidly becoming one of the most
serious problems affecting urban areas. Urban travel in
general is increasing at a rate of 4 percent per year, but
construction of new facilities is expected to accommodate
less than one-fourth of this additional demand. Therefore,
a continued loss in mobility is expected. Against this
backdrop of serious existing and growing congestion,
traffic operations' techniques and systems are needed that
can substantially increase capacity and improve tra~c-
flow efficiency. Innovative and advanced technology needs
to be incorporated into the highway system if significant
relief for urban traffic congestion is to be realized at
economic and social costs below the cost of constructing
extensive new conventional facilities. Application of ad-
vanced technologies in areas such as motorist commu-
nication, information and navigation systems, vehicle
guidance, control systems, and others has the potential
for relieving traffic congestion. To date Project 3-38~1)
has identified and assessed the most promising advanced
technologies and systems that can improve urban highway
traffic operations, and a comprehensive report on the
state-of-the art in these technologies has been prepared.
In the continuation of Project 3-38~1), funding of $42,500
will be provided towards a broad new TAB/NCR policy
study. Building on the state of the art developed under
3-3841), the TAB/NRC study (Project 3-381A will de-
velop recommendations on the appropriate staging of new
systems and the necessary research and development ac-
tivities required to bring about their implementation. The
systems to be considered range from variable-message
signs and computer-controlled traffic signals, already in
selected use, to automated highways and automatic ve-
hicle-chauffeuring systems that are in early stages of de-
velopment. The results anticipated from the study will
include an assessment of the extent to which advanced
systems could be applied to maintain and improve high-
way transportation in the United States over the next 50
years. The likely benefits and costs of specific technology
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applications, as well as options that do not involve new
technology will be estimated. Finally, a desirable schedule
for introducing stages of advanced technology, specific
research and development activities, and a funding pro-
gram will be outlined.
Project 3-38(2) FY '87
Travel Characteristics of Large-Scale Subur-
ban Activity Centers
Research Agency:
Principal Invest.:
Elective Date:
Completion Date:
Funds:
JHK and Associates, Inc.
Kevin G. Hooper
June 1, 1987
February 28, 1989
$300,000
There is a lack of up-to-date information on travel
characteristics of activity centers, particularly the large-
scale, multi-use suburban centers that have been devel-
oped recently. These data include trip generation rates,
travel modes, trip purpose, trip length, parking charac-
teristics, pedestrian activity, capture rate (i.e., proportion
of trips attracted to the development from traffic normally
passing by the site), intra-site vehicle movements, hourly
variations, and vehicle occupancy.
The objective of this project is to develop a compre-
hensive data base on travel characteristics for various
types of large-scale, multi-use suburban activity centers.
Representative trip generation rates and other travel char-
acteristics will be determined for use by others in ana-
lyzing the traffic impacts of such activity centers on the
transportation system. This research will be limited to
activity centers with over 5 million square feet of existing
floor space and that lie outside of the CBD.
The following tasks will be accomplished.
Task 1 Review existing data for purposes of identi-
fying candidate sites.
Task 2 Select activity centers. At least six sites are
to be identified for primary data collection purposes cov-
ering several different geographic areas. Travel charac-
teristics of such activity centers are believed to vary
depending on whether the center: (1) is a planned activity
center or is an assemblage of individual developments,
(2) has or does not have a regional shopping center, (3)
is located in an already built-up area within the "inner
ring" of the suburbs or is located further out where de-
velopment is still evolving, and (4) has or does not have
a significant housing component.
Accordingly, the site-selection classification scheme
will cover these factors at a minimum, as well as others
(e.g., presence of mass transit service, location on cir-
cumferential vs. radial highway, etc.) that are considered
to cause significant variations in travel characteristics.
Task 3 Develop a detailed data collection plan, iden-
tifying the data items considered to be important and
including a description of the data collection techniques,
a cost and time schedule for each center, any special
considerations for each selected center, and the data sum-
mary/presentation formats. Direct assistance in the data
collection effort from local sources will be pursued, and
identified in the plan.
Task 4 Collect data.
Task 5 Summarize data. Summaries of the data will
be designed to permit analyses of: (1) the characteristics
of the centers, (2) the intra-site trips generated by these
centers, (3) the captured trips (i.e., traffic passing by the
center with some other primary destination that stops off
for a secondary trip purpose), (4) travel characteristic
differences among multi-use centers, and (5) travel char-
acteristic differences of individual land uses within a
multi-use center relative to the same land uses when they
exist as single-use developments.
Task 6-Prepare final report. The final report will in-
clude data base summaries and an illustrative case study
to describe the application of the data to site-impact anal-
ys~s.
Tasks 1 through 5 have been completed and the final
report is in preparation: Panel review and revision will
require a time extension.
Project 3-38(3) FY '87
Traffic Adaptive Control (Phase 1)-Critical In-
tersection Control Strategies
Research Agency:
Principal Invest.:
Elective Date:
Completion Date:
Funds:
Farradyne Systems, Inc.
R. David Henry
September 1, 1988
June 30, 1989
$149,951
The inability of traditional fixed-time traffic signal con-
trol systems to automatically modify their timing plans,
in response to both long-term and short-term changes in
traffic demand, results in excessive delay and congestion.
Of particular concern is the fact that correctable delay
at poorly timed signals increases dramatically as demand
approaches capacity.
At present, there is no consensus as to the best approach
to providing traffic adaptive control in signalized net-
works. Although considerable research has been done on
strategies that periodically recompute and change system-
wide timing plans, very little research has been done with
regard to the critical intersection control (CIC) strategy
included in FHWA's UTCS software and other packages.
Preliminary results from implementation of CIC, such as
in the UTCS-enhanced-type system in Los Angeles, have
suggested its potential as an effective adaptive control
measure. However, further validation is needed. Rec-
ommendations and guidelines are needed regarding the
proper application of CIC in different types of signalized
network configurations and operating conditions.
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The objectives of this research are to: (1) determine the
effectiveness of a selected CIC strategy currently used in
a first-generation computer-controlled signal system; (2)
if the CIC strategy is shown to be effective, develop com-
prehensive guidelines and a user manual for its applica-
tion; and (3) develop detailed recommendations for
improvements to the CIC strategy for future implemen-
tation and evaluation.
To accomplish these objectives, the following tasks will
be conducted:
Task 1- A thorough review of existing CIC strategies
will be conducted. Based on this review, a CIC strategy
and potential test sitters) suitable for a comprehensive field
evaluation will be recommended.
Task 2 A field evaluation plan to determine the ef-
fectiveness of the CIC strategy selected will be developed.
This evaluation will be based on a variety of geometric
configurations, intersection spacings, traffic signal timing
and phasing, demand/capacity levels, and operational
conditions (e.g., effects on downstream intersections). Ad-
ditionally, the evaluation will determine the sensitivity of
parameters and coefficients used in the detector smoothing
algorithms and demand equations in terms of traffic per-
formance. At the completion of Task 2, an interim report
containing the results of Task 1 and the field evaluation
plan will be submitted.
Task 3 Following a decision to proceed, the field
evaluation for the strategy selected will be performed. A
report documenting the results will be submitted.
Task 4 Detailed recommendations for potential im-
provements to the CIC strategy evaluated will be devel-
oped. Examples of possible CIC improvements are (1)
ability to assign individual coefficients to specific detec-
tors, (2) ability to modify cycle length, and (3) ability to
consider congestion at downstream intersections. These
recommendations will include time and cost estimates for
implementation and evaluation in a subsequent phase of
this project.
Task 5-Following the authorization to proceed, com-
prehensive guidelines for the use of the CIC strategy
evaluated in Task 3 will be developed. These guidelines
will address issues relative to CIC applicability, con-
straints and limitations, selection of parameters and coef-
ficients used in the smoothing algorithms and demand
equations, and traffic conditions under which CIC should
be activated by the system. A user manual that documents
the guidelines in a format and style suitable for use by
operators of computerized signal systems will be prepared.
Task 6 A final report documenting all methodology
and results will be prepared.
Tasks 1 through 3 have been completed and the project
panel has met and approved a plan to conduct field tests
in the City of Los Angeles' UTCS Enhanced system. Some
computer hardware installation problems are delaying the
project, necessitating a six-month extension.
Project 3-38~4)
FY '87 and FY '88
Traffic Signal Control for Saturated Conditions
Research Agency:
Principal Invest.:
Effective Date:
Completion Date:
Funds:
KLD Associates, Inc.
Edward B. Lieberman
October 1, 1987
March31,1989
$270,000
Medium- and large-sized urban areas throughout the
United States experience saturated traffic flow conditions
on almost a daily basis. Saturated operating conditions
are characterized by the existence of queues that are not
able to discharge within a reasonable period of time at a
given signalized intersection. Signal-timing strategies
based on progression are not optimal in these situations.
Latent queues that were not able to clear during previous
cycles may cause the progression scheme to break down.
In fact, progression schemes that allow the arrival of
platoons at the rear of a latent queue may worsen the
problem by effectively lengthening the queue. These
queues may grow to sufficient length to adversely affect
upstream intersection operations. These conditions are
true during peak period (recurring) congestion and also
in nonrecurring congestion caused by special events or
incidents.
The objectives of this research are to: (1) develop a
user manual containing procedures and guidelines for
applying appropriate signal-timing strategies to minimize
the impact of recurring saturated traffic conditions under
a wide range of network geometry, traffic flow patterns,
and operating conditions; and (2) develop procedures that
can be used in computerized signal systems for real-time
response to both recurring and nonrecurring saturated
conditions.
To accomplish the first objective, the following tasks
will be conducted:
Task 1 A number of scenarios that describe saturated
conditions for a wide range of network geometry, traffic
demand, and operating conditions will be defined. Con-
sideration will be given to approach length, number of
approach lanes and their usage, pedestrian crossing re-
quirements and interference with turning traffic, actuated
and fixed-time control, upstream turning movements, and
downstream bottlenecks (e.g., bridge, tunnel, lane reduc-
tions, etc.~.
Task 2- A set of signal-timing strategies that can be
used to minimize the impact of saturated traffic flow
conditions will be prepared. Consideration will be given
to strategies that include simultaneous and reverse pro-
gression schemes and metering of upstream or side-street
traffic flow.
Task 3 For each scenario defined in Task 1, alter-
native signal-timing strategies from the set of strategies
developed in Task 2 for evaluation will be selected. Ap-
propriate signal-timing parameters (e.g., cycle length,
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phase sequencing and timing, and offsets) for each alter-
native to be evaluated will be developed. An interim report
documenting the results of Tasks 1 through 3 will be
submitted before proceeding further.
Task 4-Using the NETSIM model, the effectiveness
of the alternative signal-timing strategies developed in
Task 3 for each scenario will be evaluated. From the
analysis of these results, procedures and guidelines that
can be used by practicing engineers to select the appro-
priate timing strategy for a given set of geometric, signal-
timing, and traffic demand parameters will be developed.
Task 5 A user manual that describes the timing strat-
egies developed in Task 2 and contains the procedures
and guidelines developed in Task 4 will be developed.
Full documentation of the simulations and analysis con-
ducted in Task 4 will be included as an appendix in the
manual.
To accomplish the second objective, the following tasks
will be conducted:
Task 6 Procedures that can be used in computerized
signal systems for real-time response to both recurring
and nonrecurring congestion will be developed. These
procedures will include algorithms and detector place-
ment guidelines for determining the onset and termination
of saturation. They will also include signal-timing strat-
egies that can respond in real-time to the detection of
saturation. (The signal-timing strategies to be investigated
will not be limited to those studied in the previous tasks).
Cost and time estimates to (1) install the detectors; (2)
develop, test, and install the necessary software; and (3)
conduct before-after field evaluations at several test sites
will be prepared. These estimates will provide the basis
for a subsequent research project.
Task 7-A final report will be prepared.
Tasks 1 through 3 have been completed and the project
panel has reviewed a plan for the Task 4 scenario testing.
The research agency is revising the plan and, following
panel review and approval, work on the remaining tasks
will proceed.
Project 3-38(5) FY '88
Effective Utilization of Street Width
Research Agency:
Principal Invest.:
Elective Date:
Completion Date:
Funds:
Midwest Research Institute
Douglas W. Harwood
April 1, 1988
April 1, 1990
$160,000
New development and changing land use in many ur-
ban areas call for increases in street capacity. Frequently,
the additional capacity must be provided without an in-
crease in curb-to-curb street width. Lane-width reductions
through restriking to provide more lanes, used either
alone or in combination with parking prohibitions, me-
dian removal, and intersection improvements are among
the strategies used to provide additional capacity. Re
search is needed to document the operational effects of
narrower lane widths on congestion reduction and related
accident impacts.
The objective of this project is to determine the rela-
tionship between capacity and safety for various lane
widths and allocations for a given street width. This re-
lationship will be quantified for both street segments and
intersections. Such factors as volume-to-capacity ratios,
prevailing speeds, vehicle type and volume, alignment
quality, service to adjacent property, classification of
streets, and environmental factors are among the impor-
tant operational considerations.
To meet this objective the following tasks will be ac-
complished:
Task 1 Conduct a literature search and identify re-
lated literature on the effects of operational-type improve-
ments involving lane width on capacity and/or safety.
Task 2-Design and conduct a survey to determine
current use of narrow lane widths in urban areas. The
survey should include the rationale for or the purpose of
such use, and operating experience. The results of this
survey should identify typical types of lane-width-reduc-
tion strategies and the resulting lane configuration and
use. In addition the survey must determine data avail-
ability and quality as it relates to the selection of key
capacity and safety parameters to be studied. Finally, the
survey should identify key measures-of-effectiveness that
have been or can be used to evaluate alternative strategies.
Task 3 Develop a methodology for determining op-
erational and safety effects of narrow lane widths. The
methodology may include but need not be limited to such
techniques as: (1) field operational studies of speeds, ve-
hicle placement, and traffic conflicts, (2) traditional ac-
cident data collection and analysis, and (3) syntheses of
previous research. The overall research plan should enable
quantification of traffic performance and safety effects
over the full range of street conditions. Submit an interim
report that (1) provides a synopsis of the survey, (2)
recommends the scope of strategies to be studied, data to
be obtained, and measures-of-effectiveness, and (3) pre-
sents the methodology to further quantify the capacity
and safety effects of narrow lane widths.
Task 4-Perform studies to determine capacity and
safety effects of narrow lane widths using the methodology
developed in Task 3. Studies should include lane use (e.g.,
left-turn lane, through lane, right-turn lane), lane width,
street classification, volume-to-capacity ratio, speed, and
adjacent land use.
Task 5 Quantify the traffic performance and safety
effects of the range of lane widths for the various street
types and traffic conditions studied. Specify expected ac-
cident rates and severity along with changes in capacity
and vehicular delay.
Task 6 Prepare a final report to include an executive
summary and detailed procedures that can be used to
implement the research results. These procedures should
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include and address the following safety and operational
factors: (1) relative accident experience, (2) traffic volume
and mix, (3) relative speeds, (4) lane mix and type, (5)
street classification, and (6) relative capacity.
Tasks 1 and 2 have been completed and work is un-
derway on Task 3.
Project 3-38(6) FY ,88
Cost Sharing for Transportation Improve-
ments Near Major Suburban Employment
Centers
Research Agency:
Principal Invest:
Elective Date:
Completion Date:
Funds:
Indiana University
Thomas Snyder
May 15, 1988
August 31, 1989
$125,000
Major employment centers in suburban areas, by their
nature, generate vehicle trips that impact surrounding
road and signal facilities. Transportation improvements
are often required to mitigate impacts, sometimes at con-
siderable distance from the centers. Public agencies are
using a variety of cost-sharing approaches that in certain
cases may result in inequities, both among developers and
between the developer and the public agency. For in-
stance, a developer who triggers a threshold level for
capacity improvements may be burdened with the entire
cost. Other developers obtaining approvals before or after
the improvement costs have been allocated may not be
faced with any of these costs. Inasmuch as an equitable
agreement is in the broad public interest, it is important
that agencies and developers formulate rational positions
and derive fair-share options.
The objective of this research is to provide information
to state and local agencies, as well as developers, on (1)
how to select the most appropriate cost-sharing approach,
(2) specific factors to be considered in allocating costs in
each approach, (3) detailed cost-allocation methodologies,
and (4) application guidelines. This research will focus
on the equitable allocation of the private sector share of
transportation improvement costs among individual prop-
erties at new or expanding major suburban employment
centers.
To meet this objective the following tasks will be ac-
complished.
Task 1- Review Alternative Cost-Sharing Approaches.
Existing approaches to allocating private sector costs will
be reviewed, primarily through a literature review.
Task 2 Review Basic Economic Theory General eco-
nomic theory and principles will be reviewed for appli-
cability to the equity considerations in determining cost-
sharing allocations.
Task 3- Evaluate and Select Alternative Approaches.
Based on the results of Tasks 1 and 2, appropriate cost-
sharing approaches (e.g., impact fees, assessment districts,
negotiated agreements) will be evaluated for application
to new or expanding major employment centers and the
factors that must be accounted for in implementing each
will be identified.
Task 4 Develop Cost-Allocation Methods. For each
approach selected in Task 3, an appropriate cost-alloca-
tion method will be developed using existing methods to
the maximum extent possible. Of particular interest is the
use of sound economic theory that provides for the ap-
propriate treatment of costs (i.e., average unit costs, in-
cremental costs, marginal costs, short-term vs. long-term,
etch. Step-by-step procedures for direct application are
desired, based on empirical data to the extent possible.
Task 5 Illustrate Alternative Approaches. Use of the
alternative cost-sharing approaches and the cost-alloca-
tion methods will be illustrated by applying them to at
least three representative types of major employment cen-
ters (real or hypothetical). The same centers will be used
in each case to provide cross comparisons.
Task 6 Develop Guidelines. These guidelines should
cover (1) considerations and rationale for the selection of
cost-sharing approaches and cost-allocation methods, (2)
typical applications, and (3) limitations. The primary au-
dience for the guidelines is at the decision-making level;
whereas, the documentation of the approaches and meth-
ods should be directed to the analyst.
Research is underway on Tasks 1, 2, and 3.
Project 3-38~7) FY '89
Access Management Policies and
Guidelines for Activity Centers
Research Agency:
Principal Invest.:
Elective Date:
Completion Date:
Funds:
In developmental stage
(18 months)
$125,000
Streets and highways constitute a major public invest-
ment, and it is essential to operate them safely and effi-
ciently. Inadequate access management is an important
factor behind the operational deterioration of many of
our streets and highways. There is a need to identify better
methods for applying access management practices to
different classes of highways within the vicinity of activity
centers, and for implementing such practices on highways
experiencing access management problems.
The objective of this research is to develop policies and
guidelines to preserve and improve the capacity and safety
of the overall highway system within the vicinity of ac-
tivity centers through better management of access con-
trol. These guidelines would apply to (1) modification of
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access control on streets and highways where activity- Project 3-39 FY ,88
center development has already occurred, (2) planning
access control in newly developed areas or for new high
ways being constructed in existing developed areas, and
(3) management of access control within activity centers.
To meet this objective, the following tasks shall be
accomplished:
Task 1. Conduct a detailed review of literature, a survey
of State and local governments, and a survey of activity
center developers and managers. The purpose of these
activities in two-fold: (1) to identify problems currently
being experienced on highways and streets in the vicinity
of activity centers and (2) to identify current successful
practices for management of access to activity centers
along major streets and highways. As a minimum the
following information shall be collected:
What access management policy are in place?
Are these policies backed by legislation?
Do the policies or legislation authorize the retrofit
of access management on existing streets and high
ways within the vicinity of activity centers?
Do existing policies include access design standards?
Do access design standards vary by highway func
tional class?
How is enforcement of the policy handled?
Are standards and policy administered by State, re
gional, or local government? How is coordination
handled? How are conflicts between standards of
different jurisdictions handled?
What is the typical design year used for analysis of
access adequacy for activity centers?
What are the typical problems with current policies,
guidelines, and standards? For example, what exist
ing components should be eliminated? What existing
components should be changed? What components
should be added?
If there were no constraints (political, funding, or
personnel), what would the ideal access management
policy for activity centers include?
Task 2. Prepare a report summarizing the material
gathered during Task 1. This report shall be appropriate
for publication as a synthesis and evaluation of current
practices in access management for activity centers.
Task 3. Prepare a draft report recommending policies
and guidelines that can be used for managing access on
streets and highways in the vicinity of activity centers.
This draft report shall be circulated for review and com
ment to a representative sample of the Task 1 survey
respondents.
Task 4 At a meeting of the NCHRP project panel,
present a summary of the responses to the Task 3 draft
report and make recommendations regarding whether or
not additional research is required.
Task 5. Prepare a final report on Recommended Access
Management Policy and Guidelines for Activity Centers.
Evaluation and Calibration Procedures for
Weigh-In-Motion Systems
Research Agency: Texas A&M Research Foundation
Principal Invest: Dr. Wiley Cunagain
Elective Date: March 1, 1988
Completion Date: November 30, 1990
Funds: $265,000
State highway agencies need accurate truck-weight data
for use in planning, design, operations, and maintenance
activities related to both highway pavements and bridges.
A considerable amount of data is needed to support these
activities, as well as for enforcement and highway finance
purposes. Further, states are faced with an increasing need
for this type of information to implement pavement man-
agement systems and to meet the data requirements of
the Strategic Highway Research Program.
Various weigh-in-motion systems are available to col-
lect truck data in a more efficient manner than by using
conventional weighing methods. A number of states are
currently installing these systems and are specifying and
conducting independent acceptance and validation pro-
cedures. However, nationally recognized procedures
for acceptance testing and for on-site calibration of WIM
systems do not exist. Such procedures need to be devel-
oped and validated by statistically designed field experi-
ments so that WIM users can be confident that WIM-
estimated weights will meet specified tolerances for var-
ious applications. Widely accepted procedures will also
benefit the manufacturers by providing more consistent
testing requirements among their customers.
The objective of this research is to develop a proce-
durets), covering all WIM system applications, for (1)
acceptance testing, (2) on-site calibration, and (3) periodic
verification of system performance.
To accomplish this objective, the following tasks will
be conducted:
Task 1 Review and summarize the past experience
and technical information relating to the evaluation and
calibration of WIM systems. Prepare a task report sum-
marizing the existing information's applicability to the
objectives of this research and proposing specific proce-
dures for further development in Task 2. Each procedure
will include testing under actual traffic conditions; the
feasibility of procedures based on simulation of the traffic-
induced forces on the transducers will also be specifically
addressed, including recommendations for incorporating
this simulation into subsequent tasks.
Task 2- Develop recommended procedures for eval-
uation and calibration of WIM systems. Separate pro-
cedures may be needed for acceptance testing, calibration
at time of installation at each site, and periodic verifi-
cation. Factors to be considered include (1) types and
applications of WIM equipment, (2) site conditions, (3)
traffic mixes, and (4) a statistically valid traffic sample
Representative terms from entire chapter:
nchrp report
