TY - JOUR PY - 1987// TI - Operational effects of the longer and wider combination vehicles on the geometry of diamond interchanges JO - Transportation research record A1 - Rajappan, Bala M. A1 - Walton, Michael C. SP - 1 EP - 11 VL - 1122 IS - N2 - The Surface Transportation Assistance Act (STAA) of 1982 provided for more uniformity in size and weight regulation on federal aid highways, particularly for tractor-trailer combinations. Section 138/415 of that act also called for a feasibility study of a national intercity truck route network for commercial vehicles up to 118 ft long and 8.5 ft wide. The extra allowed length and width contributed significantly to the offtracking characteristics of these long combination vehicles (LCVs). The objective of the research described in this paper was to assess the operational impact of the LCVs on the geometry of diamond interchanges located along Interstate highways in Texas. The assessment was done by randomly sampling diamond interchanges and simulating all possible turn measurements of LCVs at their terminals. The movements were simulated with the computerized truck offtracking model (TOM).

RESULTS included the data collected on all interchanges located along Interstate highways in Texas and interval estimates of the proportion of diamonds with inadequate geometry, that is, pavement widths at ramp terminals inadequate to accommodate the LCVs. Ninety-nine percent confidence intervals were also estimated for the extra pavement widths required to prevent the LCVs from damaging pavement edges and other roadside appurtenances at the ramp terminals. Record URL: http://onlinepubs.trb.org/Onlinepubs/trr/1987/1122/1122-001.pdf TRT Terms: Axle loads; Diamond interchanges; Geometric design; Offtracking; Operations; Pavements; Ramps; Simulation; Tractor trailer combinations; Trucks; Width Uncontrolled Terms: Longer combination vehicles Old TRIS Terms: Operational effects; Pavement width; Truck pavement damage Subject Areas: Administration and Management; Design; Highways; Motor Carriers; Pavements; Planning and Forecasting; I21: Planning of Transport Infrastructure;

Language: en

LA - en SN - 0361-1981 UR - http://dx.doi.org/ ID - ref1 ER -