Research on the Vehicle Loads and Their Effect on the Medium and Small Span Highway Girder Bridges

摘要

The uniform loading pattern is specified in the General Code for Design of Highway Bridges and Culverts (JTG D60-2015) and its former version in China. In recent years, bridge safety accident due to the heavy commercial trucks occurred and reported occasionally. Whether the design loads specified in the existing code could satisfy the bridge safety in the heavy load areas is a highlighted question. Through the 24-hour traffic investigation at Xinghe segment of G6 Highway in-situ, the statistical analysis respecting to the vehicle types, vehicle numbers and the distribution of vehicles spaces are carried out. The commercial trucks weight is investigated at a typical coal storage site close to G6 Highway road. Based on the investigation data, the load patterns of the routine vehicle teams and the congestion vehicle teams are developed and proposed. Choosing the simply supported and continuous girder bridges as the case bridges, the finite element models were established using MIDAS/Civil software. The load effects under the routine vehicle team load and the congestion vehicle team load are analyzed considering 2 lanes and 3 lanes, respectively. The calculating results were compared and analyzed with the results from the coded loads in 2 lanes and 3 lanes. It was shown from the comparing analysis that the congestion vehicle team load is the potential danger for the existing bridge. The bridge design should consider the regional traffic characteristics and its development.