Study on the vibration evaluation method and allowable differential settlement of road-bridge transition section with full-car model

The differential settlement between bridge approach slab and abutment causes bump problems when vehicles passing this area. This study aims at evaluating the roughness of area between road-bridge transition properly and putting forward the allowable differential settlement value based on the comfortable feeling of passengers. In this research, the maximum transient vibration value (MTVV) was chosen to be the evaluation index of roughness vibration comfort, and full-car model and bridge approach pavement models were established using Carsim software. Then, the interactions of human-vehicle-road were simulated when the car passed the bridge at different speeds, and the influences of step height, approach slab length, approach relative slope and vehicle speed on MTVV were studied. According to the simulation results and the comfortable feeling questionnaire when a testing car passed different bridge areas, the specific grading standard of MTVV was given, and for the bridge with and without approach slab, the allowable differential slope and the step height of the bridge under difference were put forward. The results have a significant value for the roughness evaluation of the road-bridge transition area and can be used to judge whether this area is needed or not to maintain.