Low-Clearance Vehicles at Grade Crossings

摘要

A literature review revealed there are no general highway design standards aimed at providing adequate ground-clearance on highways. Similarly, there was a lack of data relative to the magnitude of the low-clearance vehicle incident problem and on low-clearance vehicle characteristics. Low-clearance vehicles, including heavy trucks plus light trucks and automobiles with trailer combinations, comprised 2.0 percent of the traffic stream. Based on the field data, a design low-clearance vehicle was proposed whose dimensions are a 36-ft wheelbase and 5-inch ground-clearance. These represent the 85th percentile of the low-clearance vehicle dimensions collected. Microcomputer software was developed to simulate the movement of trucks over high roadways so that any highway engineer can analyze low-clearance problems.