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From page 36...
... 36 This chapter presents the current AASHTO design vehicles for each vehicle type and class, summarizes available data about the current vehicle fleet, recommends updates to the dimensions of the Green Book design vehicles for consideration by AASHTO, and recommends one addition to the set of Green Book design vehicles for consideration by AASHTO. 5.1 Overview of Design Vehicles Each design vehicle presented in the Green Book is intended to represent, for geometric design purposes, an entire class of vehicles in the vehicle fleet.
From page 37...
... Updated Dimensions and Recommended Additions to the Green Book Design Vehicles 37 design purposes, all private passenger vehicles, including two-door sedans, two-door coupes, fourdoor sedans, station wagons, minivans and vans, sport utility vehicles (SUVs) , and pickup trucks.
From page 38...
... Passenger car type Number of models Vehicle length (ft) for specific passenger vehicle models Percent of passenger vehicle models for specific vehicle length ranges (ft)
From page 39...
... Vehicle make Vehicle model Vehicle type Number of Vehicle dimensions (ft) Turning circle (ft)
From page 40...
... 40 Highway and Street Design Vehicles: An Update The P design vehicle has a wheelbase of 11 ft. Table 20 shows that only 8% of passenger vehicles have wheelbases that exceed 11 ft in length.
From page 41...
... Passenger vehicle type Number of models Wheelbase (ft) for specific passenger vehicle models Percent of passenger vehicle models for specific wheelbase ranges (ft)
From page 42...
... 42 Highway and Street Design Vehicles: An Update Figure 16. Dimensions of updated passenger car (P)
From page 43...
... Updated Dimensions and Recommended Additions to the Green Book Design Vehicles 43 5.3.1 Two-Axle Single-Unit Truck The dimensions of the two-axle single-unit truck (SU-30) design vehicle are illustrated in Figure 18.
From page 44...
... 44 Highway and Street Design Vehicles: An Update 5.3.4 Single-Unit Trucks Currently Manufactured or Sold in the United States Most single-unit trucks sold in the United States have a specific wheelbase stated in the manufacturers' literature. However, a few single-unit truck models can be custom ordered with a wheelbase within a broad range.
From page 45...
... Updated Dimensions and Recommended Additions to the Green Book Design Vehicles 45 Figure 20. Recommended dimensions for updated two-axle single-unit truck design vehicle (SU-33)
From page 46...
... 46 Highway and Street Design Vehicles: An Update Source: AASHTO 2018. Figure 21.
From page 47...
... Updated Dimensions and Recommended Additions to the Green Book Design Vehicles 47 range of wheelbases to fit the truck operator's needs and the regulatory environment in which the truck will be used. For example, one particular tractor model can be ordered with wheelbases up to 40.5 ft.
From page 48...
... 48 Highway and Street Design Vehicles: An Update Figure 22. Dimensions of updated truck tractors for use with AASHTO design vehicles.
From page 49...
... Updated Dimensions and Recommended Additions to the Green Book Design Vehicles 49 Source: AASHTO 2018. Figure 23.
From page 50...
... 50 Highway and Street Design Vehicles: An Update 5.5.2 WB-62 Interstate Semitrailer The WB-62 design vehicle, shown in Figure 24, consists of a truck tractor pulling a single semitrailer cargo unit 48 ft in length. This design vehicle represents a combination truck in common use.
From page 51...
... Updated Dimensions and Recommended Additions to the Green Book Design Vehicles 51 State/District Maximum semitrailerlengths on NN (ft-in.) Alabama 53-6 Alaska 48-0 Arizona 57-6 Arkansas 53-6 California 48-0 Colorado 57-4 Connecticut 48-0 Delaware 53-0 District of Columbia 48-0 Florida 48-0 Georgia 48-0 Hawaii 48-0 Idaho 48-0 Illinois 53-0 Indiana 48-6 Iowa 53-0 Kansas 57-6 Kentucky 53-0 Louisiana 59-6 Maine 48-0 Maryland 48-0 Massachusetts 48-0 Michigan 48-0 Minnesota 48-0 Mississippi 53-0 Missouri 53-0 Montana 53-0 Nebraska 53-0 Nevada 53-0 New Hampshire 48-0 New Jersey 48-0 New Mexico 57-6 New York 48-0 North Carolina 48-0 North Dakota 53-0 Ohio 53-0 Oklahoma 59-6 Oregon 53-0 Pennsylvania 53-0 Rhode Island 48-6 South Carolina 48-0 South Dakota 53-0 Tennessee 50-0 Texas 59-0 Utah 48-0 Vermont 48-0 Virginia 48-0 Washington 48-0 West Virginia 48-0 Wisconsin 48-0 Wyoming 57-4 Source: Appendix B to 23 CFR 658.
From page 52...
... 52 Highway and Street Design Vehicles: An Update limitation, have offtracking and swept path width that is essentially equivalent to that of the WB-62 design vehicle. For this reason, the WB-62 design vehicle is often used to represent 53-ft single-trailer trucks in states with KPRA distance limitations.
From page 53...
... Updated Dimensions and Recommended Additions to the Green Book Design Vehicles 53 Intermodal container type Percentage of worldwide intermodal container commerce Intermodal container outside dimensions (ft) By total number of container units By total container capacity Length Width Height 20-ft standard vans 24 16 20.0 8.0 8.5 40-ft standard vans 14 19 40.0 8.0 8.5 40-ft high-cube vansa 38 49 40.0 8.0 9.5 Othersb 24 16 Various 8.0 Various Source: Adapted from www.LSIU.co/resources-and-links/world-container-fleet, international standard ISO 668-2013(E)
From page 54...
... 54 Highway and Street Design Vehicles: An Update Figure 27. Dimensions of updated interstate semitrailer truck design vehicle with a single 48-ft trailer (WB-64)
From page 55...
... Updated Dimensions and Recommended Additions to the Green Book Design Vehicles 55 5.6 Double-Trailer Combination Trucks The Green Book includes three design vehicles representing double-trailer combination trucks: • WB-67D -- Double Bottom Semitrailer/Trailer (see Figure 29) • WB-92D -- Rocky Mountain Double Semitrailer/Trailer (see Figure 30)
From page 56...
... 56 Highway and Street Design Vehicles: An Update also required states that previously allowed double-trailer trucks with two 28.5-ft trailers to continue to do so. This effectively established 28.5-ft trailer lengths as a minimum requirement for double-trailer trucks on the interstate system and the rest of the NN.
From page 57...
... State Maximum vehicle length (ft) Maximum length (ft)
From page 58...
... State Maximum vehicle length (ft) Maximum length (ft)
From page 59...
... Updated Dimensions and Recommended Additions to the Green Book Design Vehicles 59 • Comparisons of the maximum lengths to the dimensions of the AASHTO WB-92D and WB-109D design vehicles. The maximum vehicle length under state law is longer than, shorter than, or similar in length to the WB-92D or WB-109D.
From page 60...
... 60 Highway and Street Design Vehicles: An Update defined geographical area adjacent to the border of another state. It may be that Rocky Mountain double combinations, although legal, do not operate widely in these 11 states.
From page 61...
... Updated Dimensions and Recommended Additions to the Green Book Design Vehicles 61 Figure 32. Dimensions of updated double bottom or twin-trailer combination truck design vehicle with two 28.5-ft trailers (WB-71D)
From page 62...
... 62 Highway and Street Design Vehicles: An Update 5.7 Triple-Trailer Combination Trucks The Green Book includes one design vehicle representing triple-trailer combination trucks: • WB-100T -- Triple Semitrailer/Trailers (see Figure 35) The WB-100T design vehicle consists of a truck tractor pulling a semitrailer cargo unit 28.5 ft in length followed by two full-trailer cargo units each 28.5 ft in length.
From page 63...
... State Maximum vehicle length (ft) Maximum length (ft)
From page 64...
... 64 Highway and Street Design Vehicles: An Update states where triple-trailer trucks can operate on a reasonably large network of roads are Colorado, Idaho, Nevada, North Dakota, Oklahoma, Oregon, South Dakota, and Utah. Toll roads that allow the operation of triple-trailer trucks include the following: • Indiana Toll Road • Kansas Turnpike • Ohio Turnpike • Oklahoma Turnpikes The laws of six states permit the operation of triple-trailer trucks with trailers longer than 28.5 ft.
From page 65...
... Updated Dimensions and Recommended Additions to the Green Book Design Vehicles 65 Source: AASHTO 2018. Figure 37.
From page 66...
... 66 Highway and Street Design Vehicles: An Update Table 29 presents the data on the distribution of overall vehicle lengths for current model intercity buses, tabulated separately for two-axle and three-axle buses. The table shows that intercity buses currently on the market range in overall length from 23.50 ft to 45.80 ft.
From page 67...
... Number of axles Number of models Vehicle length (ft) for specific intercity bus models Percent of intercity bus models with overall lengths exceeding the lengths of current design vehicles Minimum Mean 90th percentile 95th percentile Maximum BUS-40 BUS-45 All types combined 33 23.50 41.78 45.58 45.59 45.80 60.6 27.3 Two axles 9 23.50 34.46 40.50 40.50 40.50 0.0 0.0 Three axles 24 40.03 44.52 45.58 45.59 45.80 83.3 37.5 Vehicle length represents the length of the vehicle body (not including appurtenances such as bicycle racks)
From page 68...
... 68 Highway and Street Design Vehicles: An Update in areas where they operate. A note will be included with the discussion of the bus design vehicles that vehicle heights up to 13.5 ft may need to be considered to accommodate double-decker buses.
From page 69...
... Updated Dimensions and Recommended Additions to the Green Book Design Vehicles 69 wheelbase shown in the Green Book for the shorter of the two design vehicles. However, this appears to result from the different relative positions of the front door and the front axle in the S-BUS-36 and S-BUS-40 design vehicles.
From page 70...
... 70 Highway and Street Design Vehicles: An Update Figure 42. Dimensions for updated conventional school bus (65-passenger)
From page 71...
... Updated Dimensions and Recommended Additions to the Green Book Design Vehicles 71 Figure 43. Dimensions for updated large school bus (84-passenger)
From page 72...
... 72 Highway and Street Design Vehicles: An Update Table 32. Total vehicle length for transit buses.
From page 73...
... Updated Dimensions and Recommended Additions to the Green Book Design Vehicles 73 Source: AASHTO 2018. Figure 48.
From page 74...
... 74 Highway and Street Design Vehicles: An Update The P/B design vehicle, shown in Figure 49, is a combination of the P design vehicle and a single-axle boat trailer with a boat in place on the trailer. The P/B design vehicle has an overall length of 42.0 ft and a width of 8.0 ft.
From page 75...
... Updated Dimensions and Recommended Additions to the Green Book Design Vehicles 75 • Class B motor homes are typically built on the chassis of a conventional van and are sometimes referred to as a campervan. • Class C motor homes are typically built on a pickup truck platform with an extended chassis to support the motor home.
From page 76...
... 76 Highway and Street Design Vehicles: An Update Motor home class Number of models Vehicle length (ft) for motor home classes Percentage of models longer than the MH design vehicleMinimum Mean 90th percentile 95th percentile Maximum Class A 134 28.42 37.33 43.75 44.96 44.96 94.0 Class B 21 19.42 22.63 24.75 24.75 24.75 0.0 Class C 130 22.08 28.20 32.50 38.69 40.17 36.2 Table 33.
From page 77...
... Updated Dimensions and Recommended Additions to the Green Book Design Vehicles 77 Trailer type Number of models Length (ft) for recreational trailers Percentage of models longer than the P/T design vehicle trailer Minimum Mean 90th percentile 95th percentile Maximum Travel trailer 1,540 10.00 30.05 38.92 40.92 45.42 55.8 Table 35.
From page 78...
... 78 Highway and Street Design Vehicles: An Update Figure 54. Dimensions for updated pickup truck and boat trailer (PU/B)
From page 79...
... Updated Dimensions and Recommended Additions to the Green Book Design Vehicles 79 • One new design vehicle, a pickup truck (PU) should be added.
From page 80...
... 80 Highway and Street Design Vehicles: An Update Table 36. (Continued)
From page 81...
... Design vehicle type Symbol Dimensions (ft) Overall Overhang WB1 WB2 S T WB3 WB4 Typical kingpin-tocenter-of-rear tandem axleHeight Width Length Front Rear Passenger car P 5.5 7.0 16.8 3.0 4.0 9.8 -- -- -- -- -- -- Pickup truck PU 6.5 7.0 20.3 3.2 4.1 13.0 Single-unit truck (two-axle)

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