Field Test of the Grade Severity Rating System

摘要

The objective of the study was to test the field effectiveness of the Grade Severity Rating System (GSRS), via application of weight-specific signs to control truck speeds on downgrades. Before-after sign effects were evaluated in terms of speed differences and incidences of smoking brakes for trucks in specific weight categories. A five-State nationwide sample of study sites included grades of varying severity. The study design included a determination of novelty effect as well as concurrent before-observations at selected control sites (i.e., no weight-specific sign present). In addition, the study examined the feasibility of state highway agencies conducting an accident study to assess GSRS safety impact. Application of the GSRS was viewed to improve States' liability positions as it represents the state of the art. Weight-specific signing was recommended for use at high severity grade locations.