Dynamic Response Analysis of Long-span Arch Bridge Under Extra-heavy Truck Load

Authors investigated the characteristics of the spatial dynamic response of an long-span arch bridge using the random traffic-bridge coupling vibration analysis software based on realistic extra-heavy truck load data recorded by the weigh-in-motion(WIM)system.A set of WIM system was installed on a bridge located in the highway from Xuanhua to Datong,Hebei Province.The extra-heavy truck load cases were defined and extracted using traffic load data in last three years acquainted by the system,then the proportions of different types and the vehicle weight distributions of the extra-heavy truck cases were analyzed,and the structure response was compared with that under the design specification load.The spatial dynamic response of longspan arch bridge under the extra-heavy truck cases was analyzed using the random traffic-bridge coupling vibration analysis software,and the structure response was compared with that under the design vehicle load in old and current bridge codes.The results show that only few extraheavy truck cases result in larger response than those under design specification vehicle load, implying that the designed load specified in the code can take into account of most critical traffic cases for the studied long-span arch bridge.