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OCR for page 66
66
uating pavement performance. Despite the importance of
distress measurements, current methods are subjective
and time consuming. However, significant progress has
been made in electronic instrumentation and in computer
technology. For example, independent efforts to fully au-
tomate crack detection, employing recent advances in
image processing and pattern recognition, are underway.
Nevertheless, ongoing efforts, even if successful, will not
resolve all the problems in fully automating distress mea-
surements. Additional work that builds on these efforts
is needed.
An increasing number of transportation agencies have
embraced the concept of data- and image-acquisition sys-
tems that record, among other things, the condition of
the pavement surface in a video format. Therefore, it is
anticipated that an automated means of processing video
images to quantify surface distress will be widely accepted
by transportation agencies. In general, the availability of
a robust image processing and pavement-distress-recog-
nition system would represent a significant contribution
in the field of pavement management at both network
and project levels.
The objective of this project is to develop a system for
processing video images to identify, quantify, and classify
pavement distress in terms of types, severity, and extent.
Accomplishment of the objective will require the follow-
ing tasks:
Task 1. Assess the potential capabilities of using video
images to identify and quantify pavement surface distress
for use in network condition assessments and for project
level decisions. Prepare a preliminary system design for
processing these video images. Specify the image reso-
lution and other characteristics required for processing,
and describe the equipment and conditions that would be
needed for obtaining such images.
Task 2. Obtain a sample of video images suitable for
the determination of pavement distress by type, severity,
and extent through automated image processing. Video
images obtained shall represent distress types across a
full-lane width.
Task 3. Develop the video image processing system
described in Task 1 with consideration for user options
on hardware and video parameters specific to an individ-
ual transportation agency.
Task 4. Validate system output by comparison with
visual interpretations of video images.
Task 5. Modify the system based on the Task 4 vali-
dations.
Task 6. Arrange to demonstrate the video image proc-
essing system to the NCHRP.
Task 7. Deliver the video image processing system soft-
ware, program source codes, and user's and program
manuals to the NCHRP.
Task 8. Prepare a final report on the total research
effort.
AREA 2: ECONOMICS
Project 2-1 FY '63 and FY '64
Criteria for Highway Benefit Analysis
Research Agency: University of Washington
Principal Invest.: Prof. R. G. Hennes
Effective Date: June 1, 1963
Completion Date: November 30, 1967
Funds: $101,948
This project provided estimates of the relevance of dif-
ferent types of benefit and cost data to decisions in high-
way location. Basic guides for priorities, guidelines for
data collection, and basic information related to taxation
were developed.
An interdisciplinary approach to the problem was un-
dertaken by the Departments of Civil Engineering, Po-
litical Science, Business Administration, Economics, and
Sociology of the University of Washington.
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 2-2 FY '63
Guidelines for the Determination of Commu-
nity Consequences
Research Agency: University of Washington
Principal Invest.: Prof. Edgar M. Horwood
Elective Date: July 1, 1963
Completion Date: August 31, 1964
Funds: $48,873
This project was concerned with identifying and pre-
dicting community consequences arising from highway
improvements. It was designed to seek out both favorable
and unfavorable consequences and involved evaluation of
existing economic impact studies, developing of guidelines
for highway agencies to follow in these studies, and the
outlining of urgent aspects of this problem needing de-
tailed researched.
The Urban Planning and Civil Engineering Depart-
ments combined their talents and analyzed more than 600
research reports and other writings. The final report pre-
sented an analysis of bypasses, circumferentials, and radial
freeway impact effects. The utility of these studies, as well
as expressed gaps in knowledge, was also discussed.
This research has been completed, and the results have
been published as: NCHRP Report 18, "Community Con-
sequences of Highway Improvement."
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67
Project 2-3 FY '63 and FY '64
Analysis of Motor Vehicle Accident Data as
Related to Highway Classes and Design
Elements
Research Agency:
Principal Invest.:
Elective Date:
Completion Date:
Funds:
Cornell Aeronautical Laboratory
Dr. J. K. Kihlberg
June 1, 1963
August31,1966
$155,972
The objective of the study was to determine the rela-
tionship of motor vehicle accidents to highway design
elements. The study consisted of two phases: Phase 1 was
a one-year study to detains accident and severity rates
for various highway types; Phase 2 was a two-year study
to extend these rates to various geometric elements of the
highway.
The research has been completed, and the project report
has been published as: NCHRP Report 47, "Accident
Rates as Related to Design Elements of Rural Highways."
Project 2-4 FY '63 and FY '64
The Value of Highway Travel Time, Comfort,
Convenience, and Uniform Driving Speed
Research Agency:
Principal Invest.:
Effective Date:
Completion Date:
Funds:
Texas A&M University
Research Foundation
Dr. W. G. Adkins
June 1, 1963
August 31, 1966
$77,100
Various methods that have been proposed to evaluate
time savings accruing to highway vehicles are reviewed
in this report, and two selected models were used to
analyze Interstate Commerce Commission data on com-
mercial highway carriage for the year 1962. Values of
time saving in dollars per hour were derived for nine
geographical regions as designated by the Interstate Com-
merce Commission for cargo vehicles and for intercity
buses. Detailed methodology of the cost-savings model is
presented so that other researchers can make similar es-
timates under known local conditions. Also, an updating
technique has been developed, and the 1962 costs were
projected to 1965 utilizing equipment costs and driver
wags and benefit indexes to develop multipliers. The as-
sumptions of this technique and the limitations of apply-
ing the derived results are discussed.
The final report for this project has been published as:
NCHRP Report 33, "Values of Time Savings of Com-
mercial Vehicles."
Project 2-5 FY '63 and FY '64
Running Cost of Motor Vehicles as Affected
by Highway Design and Traffic
Research Agency: The Catholic University of America
Principal Invest: Dr. Paul J. Claffey
Elective Date: June 1, 1963 June 1, 1965
Completion Date: Aug. 31, 1964 Dec. 31, 1966
Funds: $49,998 $51,265
In this project, the motor vehicle running costs were
developed for use in evaluating user costs related to pro-
posed highway improvements and traffic regulations.
These costs were determined from actual vehicle field tests
as well as from the available literature.
A research report presenting the results of the first
year's work was received and has been published as:
NCHRP Report 13, "Running Cost of Motor Vehicles
as Affected by Highway Design."
This report relates the fuel consumption cost of a typ-
ical passenger vehicle to various roadway geometries and
operating characteristics as measured by more than 4,000
test runs in the field. It describes the development of a
precise fuel meter used to collect the data. Brief studies
are reported on oil consumption, maintenance, tire wear,
and depreciation costs as they are affected by highway
and traffic conditions.
During the second phase of research, fuel and time
consumption data were collected for a second passenger
vehicle, a transit bus, a tractor semitrailer, a single-unit
truck, and a diesel truck. A special fuel meter for mea-
suring the fuel consumption of diesel trucks was devel-
oped.
The results of this project have been combined with
the results of Projects 2-5A and 2-7. The findings of the
combined research effort have been published as: NCHRP
Report 111, "Running Costs of Motor Vehicles as Af-
fected by Road Design and Traffic."
Project 2-5A FY '65 and FY '67
Running Cost of Motor Vehicles as Affected
by Highway Design and Traffic
Research Agency:
Principal Invest.:
Effective Date.
Completion Date:
Funds:
Paul J. Claffey and Associates
Dr. Paul J. Claffey
July 1, 1967 Aug. 11, 1969
Dec. 31, 1968 Aug. 10, 1970
$35,000 $30,665
The original 2-5 project was continued to obtain more
detailed data on running costs of motor vehicles in order
to eliminate certain gaps that exist in the information
available on this subject. The results of the earlier work
on Project 2-5 and Project 2-7 have been combined with
the additional results of this phase of the project into a
single comprehensive final report. The erects that vari
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68
ations in gradient, road surface, speed-change frequency,
and traffic volumes have on the running costs of passenger
cars, pickup trucks, two-axle six-tire trucks, and tractor-
trailer combinations are included in the final report, and
information is provided on the operating expenditures of
fuel and oil consumption, maintenance and depreciation,
tire wear, and accidents. Condensed graphs of the findings
of the fuel consumption and tire wear studies are pre-
sented. Each is designed to provide fuel and tire wear
cost for various combinations of road design elements and
speed-change conditions for a given running speed. Also
included are families of curves of fuel consumption and
tire wear for the eleven test vehicles used in the study
and data on the maintenance costs of passenger cars and
trucks relative to travel distance, together with average
oil consumption rates for operation on dust-free pave-
ments in free-flowing traffic, on dustry roads, in free-
flowing tragic, and on high-type pavements under restric-
tive traffic conditions. Several appendices detail a com-
parative analysis of fuel consumption of diesel and
gasoline trucks, determination of the excess fuel consumed
by passenger car passing maneuvers, an investigation of
devices for the measurement of tire wear, development
of equipment for the measurement of vehicle fuel con-
sumption, and an annotated bibliography on highway
motor vehicle operating costs.
The final report for this project has been combined
with those from Projects 2-5 and 2-7 and published as:
NCHRP Report 111, "Running Costs of Motor Vehicles
as Affected by Road Design and Tragic."
Project 2-6 FY '63 and FY '64
Warranted Levels of Improvement for Local
Rural Roads
Research Agency:
Principal Invest.:
Elective Date:
Completion Date:
Funds:
Stanford University
Prof. C. H. Oglesby
June 1, 1963
September 30, 1966
$40,000
This project was concerned with the setting of economic
standards for the construction and maintenance of local
rural roads. The research has been completed, and the
results have been published as: NCHRP Report 63,"Eco-
nomics of Design Standards for Low-Volume Rural
Roads."
Project 2-7 FY '64 and FY '65
Road User Costs in Urban Areas
Research Agency:
Principal Invest.:
Elective Date:
Completion Date:
Funds:
The purpose of this research was to provide data on
road-user costs as classified by arterial type, operating
speed, traffic composition, and delay factors. Basic tables
applicable for planning and for selecting arterial street
and highway systems from the various alternates in urban
areas were developed.
The final report contains information on fuel and time
consumption rates of a passenger vehicle, two trucks, and
a bus operating on various types of urban facilities under
various levels of service. Some study was devoted to de-
termining motor vehicle accident costs and oil and main-
tenance costs which can be attributed to urban driving
conditions. Tire wear data were collected for freeway and
urban arterial comparisons.
The results presented in the project report have been
combined with the results of Projects 2-5 and 2-5A and
published as: NCHRP Report 111, "Running Costs of
.
Motor Vehicles as Affected by Road Design and Traffic."
Project 2-8 FY ,64
Estimation and Evaluation of Diverted and
Generated (Induced) Traffic
Research Agency:
Principal Invest.:
Elective Date:
Completion Date:
Funds:
Northwestern University
Prof. W. L. Garrison
May 1, 1964
August 31, 1966
$40,000
Traffic volumes on new or improved highway facilities
are found to increase more than can be attributed to
normal growth of existing traffic. This extraordinary
traffic increase is composed of two components, diverted
and generated. In making analyses of highway improve-
ment consequences, such diverted and generated traffic
must be taken into account. At the present time, sufficient
information is not available concerning characteristics of
this type of traffic.
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 2-9 FY ,66
Effect of Highway Landscape Development on
Nearby Property
Research Agency:
Principal Invest.:
Elective Date:
Completion Date:
Funds:
The Catholic University of America
Dr. Paul J. Clayey
February 1, 1964
May 31, 1966
$99,376
The Franklin Institute
Joel N. Bloom
November 8, 1965
January 31, 1968
$149,103
The intent of this research was to study how highway
landscape development affects nearby property on a na-
tionwide basis. This study determines the comparative
effects of different basic types of landscape treatments in
regard to property values, land use compatibility, and
OCR for page 69
general acceptability. Factors relative to the problem in-
clude geometric design as well as plantings, fencing, slope
blending, and screening applications.
The report will assist highway engineers and landscape
architects in developing designs that will reduce highway
noise levels to an acceptable range for adjacent residents.
The research results have been published as: NCHRP
Report 75, "Effect of Highway Landscape Development
on Nearby Property."
Project 2-10 FY '67
Future Needs for Oversize-Overweight Permit
Operation on State Highways
Research Agency:
Principal Invest.:
Effective Date:
Completion Date:
Funds:
Roy Jorgensen and Associates
Ralph D. Johnson
November 1, 1966
April 30, 1968
$99,655
The purpose of this study was to evaluate the extent
of current and future activities of oversize-overweight
vehicles in relation to the highway transport situation.
The research results have been published as: NCHRP
Report 80, "Oversize-Overweight Permit Operation on
State Highways."
Project 2-11 FY '67
Summary and Evaluation of Economic Con-
sequences of Highway improvements
Research Agency:
Principal Invest.:
Effective Date:
Completion Date:
Funds:
Highway Research Board
Robley Winfrey
January 1, 1967
July 31, 1970
$110,000
This project reviewed the reports submitted on eco-
nomics in NCHRP, as well as information from other
sources, and prepared the results in a form that may be
used directly by engineers, economists, and others who
wish to make highway economic studies.
The research was conducted in four phases: (a) to pre-
sent the background and principles of engineering econ-
omy and economic analysis; (b) to present the findings
of Projects 2-1 to 2-9, together with supplementary data
from other sources, in an organized form for use in benefit-
cost studies and other economic analyses; (c) to identify
gaps in the information available and needed research to
fill these gaps; and (d) to make an introductory study of
probable future trends in the technology of economic
analysis.
The project report has been published as: NCHRP
Report 122, "Summary and Evaluation of Economic Con-
sequences of Highway Improvements."
Project 2-12 FY '73 and FY '77
Highway User Economic Analysis
Research Agency:
Principal Invest.:
Effective Date:
Completion Date:
Funds:
Stanford Research Institute
D. G. Andersen
Apr. 1, 1974 Oct. 11, 1976
Oct. 31, 1975 May 31, 1977
$90,074 $9,995
The 1960 AASHO "Informational Report by Com-
mittee on Planning and Design Policies on Road User
Benefit Analyses for Highway Improvements" (updated
revision of the original 1952 report) was written to provide
a simple, easy-to-use method for carrying out economic
analyses on highway alternatives by those having only
basic knowledge of principles of economics. The objective
of this research was to employ, to the best possible extent,
current empirical data on highway user benefits and costs
(such as from NCHRP Report 122 and other research)
to provide a revised and updated version of the 1960
AASHO publication. The revised version includes an
analysis methodology based on sound economic theory
and is suitable for immediate, direct application. The
methodology provides a means of evaluating public transit
operating on public highways. This evaluation allows
comparisons between transit operation and additional
highway improvements. Further, procedures are included
that provide the user with a means for periodic updating
of the numerical factors and cost coefficients through
utilization of commonly available economic data. A1-
though it was recognized that environmental and social
factors are significant items of input to the decision-mak-
ing process, this research was limited to road user benefits
and costs only.
The final report, "A Manual on User Benefit Analysis
of Highway and Bus Transit Improvements," has been
published by AASHTO and can be obtained by writing
to: American Association of State Highway and Trans-
portation Officials, 444 North Capitol St., N.W., Suite
225, Washington, D.C. 20001
Project 2-13 FY ,83
Multilane Design Alternatives for improving
Suburban Highways
Research Agency:
Principal Invest.:
Elective Date:
Completion Date:
Funds:
Midwest Research Institute
Douglas W. Harwood
July 18, 1983
March 31, 1985
$100,000
The objective of this research was to investigate and
compare the safety, operational, and cost characteristics
of selected multilane design alternatives for use in sub-
urban areas. Operational characteristics include capacity,
level of service, and accessibility. Alternatives to be in-
vestigated include:
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70
. Three-lane with two-way left-turn lane.
. Four-lane divided with one-way left-turn lanes in the
median.
. Four-lane undivided.
. Five-lane undivided, including a center two-way left-
turn lane.
Each alternative was investigated under both a no-shoul-
der condition and a full shoulder condition. Of particular
concern were highways with traffic volumes over 7,000
vehicles per day and speeds between 35 and 50 mph (i.e.,
these conditions usually indicate that a 2-lane highway
can no longer handle the traffic demand).
A set of critical factors was identified that should be
considered in making meaningful comparisons of the var-
ious highway types. The following factors were consid-
ered: median presence; shoulder width; accessibility to
roadside developments; right-of-way requirements; ca-
pacity; operational characteristics; and accident experi-
ence. Accident data were obtained from California and
Michigan and operational data were developed by the
University of Nebraska using a computer simulation
model.
The relative merits of each highway design alternative
were described in terms of operations, safety, and costs.
Primary advantages, disadvantages, and limitations of
each alternative were delineated. An example was devel-
oped to illustrate how all of the identified factors would
typically be considered by state or local authorities in the
selection of a particular design. This example demon-
strates the general approach, rather than a rigid meth-
odology, to the selection process.
The final report has been published as NCHRP Report
282.
Project 2-14 FY '86
Public/Private Partnerships for Financing
Highway improvements
Research Agency: Kimley-Horn and Associates
Principal Invest.: Laurence J. Meisner
Elective Date: January 1, 1986
Completion Date: March 31, 1988
Funds: $125,000
The objective of this research was to provide guidance
to state and local highway officials and private developers
on existing and potential public/private partnership
mechanisms, including present state and local statutes
and ordinances related to private (e.g., developer) partic-
ipation in financing highway improvements. The project
has identified constraints on private participation in fi-
nancing highway and road improvements, identifies po-
tential opportunities and appropriate processes to
implement public/private partnerships, and documents
examples of state and local legislation enabling and en-
couraging such partnerships. Guidelines have been de
veloped for application at the state and local levels to
facilitate this form of highway financing.
The guidelines consist of a well-defined, step-by-step
process which can be used at the State or local level to
implement legislation to facilitate public and private fi-
nancing partnerships. Specific examples of legislation in-
clude recommended language for both statutes and
ordinances for three of the most promising mechanisms,
namely, special assessment districts, impact fees, and de-
velopment agreements. A benefit-cost analysis technique
was also developed for analyzing benefits to the public
and private sectors of a potential funding arrangement.
All research has been completed. NCHRP Research
Results Digest 161, "Public and Private Partnerships for
Financing Highway Improvements," has been published
as a separate report covering only the legal issues.
The final report has been published as NCHRP Report
307, "Public and Private Partnerships for Financing
Highway Improvements."
Project 2-15 FY '86
Identifying Measuring, and Evaluating the
Benefits of Safety Roadside Rest Areas
Research Agency: KLD Associates, Inc.
Principal Invest.: Gerhart F. King
Effective Date: January 13, 1986
Completion Date: September 30, 1989
Funds: $236,560
There is no known reliable and generally accepted
method for measuring and evaluating the benefits of safety
roadside rest areas. Most states have not yet completed
the originally planned rest area system and now also face
the necessity of major reconstruction of many older rest
areas.
Rest areas are very popular with the traveling public.
Recent sharp increases have occurred in both construction
and operation costs of rest areas, and competition for
funding with other highway construction and mainte-
nance programs has become difficult. Therefore, the need
is extremely great for a reliable and accepted method of
comparing rest area benefits with costs. A study is nec-
essary to identify (1) how state highway agencies benefit
from rest areas, (2) users and nonusers and how they
benefit, and (3) the value of these benefits and related
costs.
A new profile of rest area users and their needs is
necessary to properly evaluate existing facilities, and to
plan and design new and reconstructed rest areas.
The makeup of rest area users today has changed since
rest areas were first built. Driving habits are different,
motorists' attitudes toward mobility have changed, and
there is an increasingly more mobile public, e.g., senior
citizens, handicapped, and young families. Furthermore,
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71
traffic speeds and conditions have changed, along with
vehicle types and sizes.
While rest area benefits are viewed in a variety of ways,
safety is typically near the top of the list. Investigation
of experience in managing and operating highway systems
with rest areas, including those with commercial facilities,
and those systems without rest areas may provide useful
data on driver fatigue, behavior, and accident patterns.
The objective of this research is to develop a method
for measuring and evaluating the benefits of roadside rest
areas to result in more cost-effective designs and opera-
tions. This research will address both the benefits and
disbenefits associated with rest area facilities.
The research will include the following tasks:
Task 1 Review relevant domestic and foreign pub-
lications and research findings.
Task 2 Determine present practice and experience
among the states and other appropriate sources in cost
and benefit analyses relative to the planning and man-
agement of roadside rest area programs.
Task 3 Develop a profile of rest area users and their
needs. The user profile should reflect the current mix of
rest area users as well as forecasted trend changes over
the anticipated 20-year service life of the facilities.
Task 4 On the basis of an evaluation of the methods
identified in Tasks 1 and 2 and the profile developed in
Task 3, develop a preliminary cost/benefit analysis
method for general application. This method will identify:
. How state highway agencies benefit from rest areas.
. How users benefit and who they are.
. How nonusers benefit and who they are.
. The value of these benefits and related costs.
The method should be comprehensive and cover (1)
rest area user needs, (2) functional attributes of rest areas
(e.g., safety, comfort, inflation, security, maintain-
ability, aesthetics), (3) resultant economic benefits or dis-
benefits to the user, community, tourism, local business,
state economy, etc., and (4) the capital and operating
costs. The method should consider the type of users (e.g.,
trucking, recreational), type of highway, location (rural/
urban), vehicle mix, cooperation with adjoining states,
speed limit, and it should be applicable to both new proj-
ects and rehabilitation of existing rest areas. Who pays
and who benefits should be specifically addressed, as well
as innovative funding approaches including private fund-
ing, joint use, etc.
Safety is considered to be a primary factor in the de-
cision to provide rest areas. This research will identify
and quantify, to the extent possible, the safety elements
provided by rest areas. Practical operating problems such
as seasonal fluctuations in demand, personnel turnover,
and the like, are also of interest.
Although quantification of benefits and disbenefits is
desired, many factors are too subjective to develop precise
quantitative values. Therefore, the method should provide
some means, such as a subjective ranking scheme, to
address these factors. For example, the priority or em-
phasis a particular state or area places on the desire to
promote tourism could be factored into the analysis.
In relating benefits to costs, the method should include
a level-of-service concept. In effect, the benefits of a basic
rest area (only parking and restrooms) should be assessed
in relation to its cost, as well as incremental additions
(e.g., picnic areas, information facilities, sanitary dumping
facilities).
Task 5-Prepare an interim report that discusses the
preliminary method developed in Task 4.
Task 6 Design a process to conduct a rest area cost/
benefit analysis incorporating the method developed in
Task 4, and apply this process to an actual case study.
The process should (1) reflect the public's perception
of what a rest area should be, (2) have wide application,
(3) lead to more cost-effective programs and facility de-
signs, and (4) be clear, easily applied, reasonable, and
acceptable to highway agencies and the public.
Task 7 Prepare a final research report as well as a
handbook to assist managers in applying rest area cost/
benefit analysis. The handbook will include the case study
to illustrate how the process is applied.
Tasks 1 through 5 have been completed. The project
panel has reviewed a draft "Rest Area Analysis Meth-
odology" (RAAM). The RAAM is now being applied to
a case study on Interstate 81 in Virginia under Task 6.
All work is expected to be complete by mid-1989.
Project 2-16 FY '87 and FY '89
Relationships Between Vehicle Configura-
tions and Highway Design
Research Agency:
Principal Invest.:
EJ~ective Date:
Completion Date:
Funds:
Transportation Research Board
Robert E. Skinner, Jr.,
Joseph R. Morris
March 2, 1987
June 30, 1990
$900,000
Data from the AASHO Road Test and other field ex-
perience indicate that most pavement distress and damage
are associated with heavy axle loads from highway ve-
hicles. Specifically, the Road Test data show that pave-
ment damage increases exponentially as axle loads get
heavier. Analysis of the Road Test Data also indicates
that increases in pavement thickness permit exponential
increases in equivalent axle loads for comparable pave-
ment perfol~ance. Mr. F. C. Turner, retired FHWA
Administrator, has suggested that use of longer trucks
with more axles and lower axle loads could result in
reduced damage to pavements and more efficient use of
transportation funds. Considerable interest has developed
in investigating Mr. Turner's suggestion.
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72
This is a very complex issue involving technical, eco-
nomic, social, and other factors. No detailed systematic
evaluation has been made of the influence of vehicle con-
figurations (e.g., axle loads, axle spacing, tire pressures,
and spring components) and highway design (e.g., pave-
ment thickness, bridges and geometries) on the efficiency
of the highway transportation system.
The overall objective of this project is to develop rec-
ommendations for coordination of heavy vehicle config-
urations and pavement, bridge, and highway geometric
design to produce the most practical and efficient trans-
portation of goods and services over the highway system.
The initial phase of the research (1) collected, reviewed,
and evaluated available information pertaining to the
problem; (2) conducted a pilot analytical study involving
the more significant factors and sample data; and (3)
assessed the feasibility and practicality of further devel-
opment of an optimum solution. The end product of the
initial research phase consisted of recommendations for
further research intended to produce (1) short-term im-
provements in interactions of heavy vehicles with the
existing highway system having potential for early im-
plementations, and (2) long-term optimization of the
heavy vehicle-highway design interaction intended to pro-
duce improved efficiency of the highway transportation
system.
The initial phase of this research has been completed
as NCHRP Project 20-7, Task 27, which concluded that
the "Turner" proposal does appear feasible and that it
may yield important benefits to all road users, but that
further examination is necessary in the areas of carrier
acceptance, alternative vehicle configurations, potential
safety impacts, the costs of added bridge stress, and pave-
ment wear effects under varying assumptions concerning
which roads the new trucks would be allowed to use.
The second phase of the project, now well underway,
will consist of five objectives to: (1) estimate, based on
actual experience under similar circumstances, how car-
riers would use the new truck configurations; (2) com-
prehensively evaluate effects on bridges that could result
from the new truck sizes; (3) analyze the safety of the
new trucks compared with the vehicles they would re-
place; (4) refine the pavement impact estimates of the
feasibility study; and (5) provide guidance to the states
and the federal government on the costs and benefits of
alternative truck size and weight regulations. The results
of the study's second phase should be useful guidance to
public agencies on vehicle regulations that will allow more
efficient transportation.
Research on all major objectives is proceeding on sched-
ule. The study committee met on September 7, 1988 to
review progress and provide direction to the researchers.
Drafts of some chapters of the final report are already
under development. A complete draft report is scheduled
for August 1989.
Project 2-17 FY tso
Transportation and Economic Development
Research Agency:
Principal Invest.:
Elective Date:
Completion Date:
Funds:
In developmental stages
(24 months)
$250,000
The role of an effective transportation system in build-
ing and maintaining a vital economy has been recognized
as a critical issue and is currently the subject of renewed
interest. It is generally recognized that there is a need for
better understanding of the various relationships between
transportation decisions (e.g., capital investments, regu-
latory actions, and taxing and pricing policies) and eco-
nomic development. These relationships can be important
in terms of both the net effect of the transportation system
on the national economy and the impact on local and
regional economies. At the national level, a 1988
AASHTO working draft, "The Bottom Line," states,
"Transportation has always been a major driver of eco-
nomic development and productivity. In the contempo-
rary economy (service oriented, internationally oriented)
it is less clear in what ways transportation can support
the national economy. New travel patterns and new eco-
nomic demands are being made and the transportation
system must be prepared to respond. In the service econ-
omy transportation's role is different rather than de-
creased. There may well be fewer ton-miles per capita,
or per dollar of GNP, in the future economy, but there
will be ton-miles of very high value goods, with rigid
delivery schedules and rapid travel time requirements.
The demands for high quality services with assured re-
liability will be great. The mobility of our citizens and
foreign visitors will be a crucial future economic resource.
The economic power of tourism, and the importance of
rapid access to all points of the country by business trav-
elers, are just beginning to be appreciated. Recognition
of the new roles of transport, and particularly surface
transport, are only slowly permeating into public policy.
The link between transport investment and succeeding
economic development and productivity has not yet been
generally recognized in policy formation. The objective
of this research, at the national level, will be to gain insight
into the relationship between transportation and the na-
tion's economic vitality and competitiveness. At the State
and local level it is important for decision makers to have
reliable estimates of the economic health and productivity
benefits of potential transportation investments or man-
agement actions at the local and regional levels. The
objective of this portion of the research is to produce a
synthesis of current practice and an evaluation of methods
used by planners at the state level in carrying out re-
sponsibilities such as the following: prioritizing highway
improvement projects based on economic considerations,
Representative terms from entire chapter:
nchrp report
