Geometric Design Practices for Resurfacing, Restoration, and Rehabilitation (2011) / Chapter Skim
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From page 11... ...
This chapter will discuss state practices with regard to specific geometric design criteria. STATE PRACTICES AND PROCEDURES How Many States Have a Formal 3R Policy?
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From page 12... ...
Targeted improvements include the addition of protective devices, such as metal beam guard rail, and cost-effective safety improvements include relatively low cost devices such as signing and striping. If the Safety Screening results in the determination that more extensive safety work is required, then the project will be identified as a 3R project.
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From page 13... ...
The Preservation standard is the existing condition or the New Construction/Reconstruction standard, whichever is less, for each of the 13 controlling design elements. Exempt projects include Pavement Preventive Maintenance projects, which apply where the pavement is in good condition with significant remaining service life.
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From page 14... ...
TABLE 2 3R GUIDELINES FOR NHS AND NON-NHS IN WEST VIRGINIA Design Element Nonfreeway NHS Non-NHS Design Speed Use existing speed limit Speed study to determine Horizontal Curvature/Superelevation Consider variety of nongeometric changes; refer to Vol. 7 of NCHRP 500 Same Vertical Alignment Review for possible reconstruction if safety deficiencies and if cost-effective Same but also adds condition that ADT > 2,000 Lane and Shoulder Width Specific values for divided and undivided arterials Refers to NCHRP Report 362; widen only if accident rate can be reduced; minimum values are less than NHS Cross Slope and Superelevation Cross slope minimum of 1.6%; meet AASHTO standards if crash history Same as NHS Vertical Clearance 14 ft 13 ft 6 in.
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From page 15... ...
Alabama 9 Arkansas 12 to 15 California 48 Florida 36 Idaho 24 Illinois 24 Indiana 12 to 24 Iowa 24 Kansas 36 Kentucky About 12 Louisiana 12 Maine 9 Maryland 12 Michigan 12 Minnesota 22 Missouri 20 Nebraska 30 Nevada 12 New Hampshire 16 to 24 New Mexico 18 New York 30 North Dakota 24 Ohio 12 Oklahoma 9 Oregon 30 Pennsylvania 8 Rhode Island 12 South Dakota 12 to 24 Texas 14 Utah 2 Vermont 24 to 60 Virginia 8 to 30 Wisconsin 24 to 48 Wyoming 36 TABLE 3 NUMBER OF 3R PROJECTS AND LANE MILEAGE PER YEAR State Average Number 3R Projects Each Year Average Lane-Miles Treated Each Year Average Lane-Miles per Project Michigan 600 7,000 12 Georgia 550 1,300 2 Alabama 500 4,800 10 Wisconsin 400 1,500 4 Missouri 250 6,000 24 Maryland 200 1,000 5 Texas 200 5,000 25 Louisiana 165 1,450 9 Florida 150 2,000 13 South Dakota 130 no response N/A Minnesota 88 521 6 Idaho 80 160 2 Indiana 75 200 3 Nebraska 70 1,240 18 Utah 48 no response N/A Iowa 35 400 11 Pennsylvania 35 150 4 New York 12 210 18 Oregon 12 400 33 New Mexico 10 100 10 Wyoming 10 40 4 Illinois 9 25 3 Arkansas 7 7 1 Kentucky 5 100 20 North Dakota 5 50 10 New Hampshire 4 75 19 Ohio 3 30 10 Puerto Rico 3 40 13 Rhode Island 3 5 2 Kansas 2 8 4 Vermont 2 5 3 N/A = not available. What Is the Average Duration to Progress a 3R Project from Conception to Start of Construction?
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From page 16... ...
The extent of the deterioration will influence the decision on whether a project should be designed using the 3R design criteria or whether it should be designed using reconstruction criteria." Illinois has a nearly identical statement, but goes on to state, Whenever the proposed pavement improvement is major, it may be practical to include significant geometric improvements (e.g., lane and shoulder widening) in the project design.
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From page 17... ...
Colorado's policy is that the Headquarters Safety and Traffic Engineering Branch must perform a safety evaluation for all 3R projects. The safety evaluation is to consider all 13 geometric design criteria for the entire project and complete design exception variance requests as needed.
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From page 18... ...
The designer is to coordinate with the district traffic engineer to determine if the project includes locations with known safety issues, based on the Division of Highway's tracking system prioritized safety improvements list. The 3R policy directs the designer to the NHCRP Report 500 series and the AASHTO Strategic Highway Safety Plan (as of the preparation of its 3R policy, West Virginia had not yet prepared its own Strategic Highway Safety Plan)
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From page 19... ...
Other items further down the list are imporTABLE 7 RANKING OF CONTROLLING DESIGN ELEMENTS Design Criteria Number of Times Ranked From 1 to 13 Average Ranking 1 2 3 4 5 6 7 8 9 10 11 12 13 Lane Width 9 11 4 9 6 1 1 4 2 0 0 1 0 3.8 Shoulder Width 3 8 8 7 8 5 3 0 2 3 0 0 1 4.6 Design Speed 19 5 0 4 2 5 3 1 1 1 1 2 4 4.6 Stopping Sight Distance 4 4 9 1 4 5 7 5 4 1 2 0 2 5.8 Horizontal Alignment 2 4 7 2 4 3 6 7 4 3 5 0 1 6.4 Structural Capacity 7 5 2 1 3 6 3 2 3 1 3 7 5 7.0 Superelevation 1 1 3 7 3 6 4 6 5 2 3 3 2 7.1 Bridge Width 0 1 3 4 8 4 4 4 6 5 6 3 0 7.4 Vertical Alignment 0 1 4 5 0 6 4 8 6 5 4 4 1 7.7 Cross Slopes 1 3 3 2 3 4 4 4 2 8 7 2 5 8.1 Horizontal Clearance 1 0 3 2 5 1 2 2 4 4 5 13 6 9.3 Vertical Clearance 1 3 2 3 2 1 3 1 2 4 7 4 15 9.3 Grades 0 2 0 1 0 1 2 4 7 11 5 9 6 9.9 The FHWA report Good Practices: Incorporating Safety into Resurfacing and Restoration Projects (13) is a good resource for how states can include low-cost safety improvements in their 3R projects.
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From page 20... ...
Given that stopping sight distance is one of the 13 design criteria, presumably the respondents were referring to the corner sight triangle distances need for turning left or right or crossing the intersection. Adding the five states that mentioned other intersection design elements (five responses)
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From page 21... ...
Pedestrian, Bicycle, and ADA Requirements • When are projects exempt from improving bicycle and pedestrian accommodations? • To what extent beyond signalized pedestrian crossings should such facilities be upgraded for ADA compliance?
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