Analysis of Vehicle Load Effect on Long-Span Bridge under Mixed Traffic Flow

Abstract:

Truck platooning is a traffic mode that can realize close distance following between trucks through automatic control， wireless communication， and other technologies. The decrease of gap directly leads to the increase of heavy vehicle density. Moreover， long-span bridge can accommodate a large number of truck platoons， which may affect the whole or partial structure. To study the load effect of truck platooning and mixed traffic flow composed of ordinary vehicles and truck platoons on bridge structure， and the applicability of the current design code， this paper investigated the actual test and theoretical research on truck platooning at home and abroad， and proposed a load model for truck platooning and a simulation method for mixed traffic flow based on the measured traffic flow data of long-span bridges in service. The mixed traffic flow simulation of a long-span suspension bridge was conducted， considering the actual operation condition of the bridge. In addition， the vehicle load effect level and safety of the bridge in the representative mixed traffic scenarios were studied， and the influence of truck platooning mode and mixed traffic flow on the vehicle load effect of the long-span suspension bridge was analyzed. The results show that the load effect of mixed traffic flow is significantly higher than that of ordinary vehicle traffic flow， but it is still lower than the code value. The effect value under different loading scenarios is about 35%~80% of the code value， indicating that the current code can provide a good safety margin for the global effect and partial effect of structure under mixed traffic flow with the participation of truck platooning， and that the safe service of the bridge can be ensured under the corresponding operation conditions in the future.

Key words:long-span bridge;vehicle load;mixed traffic flow;truck platooning;global effect;partial effect