DYNAMIC PERFORMANCE OF A CABLE-STAYED CONCRETE-FILLED STEEL TUBE ARCH BRIDGE UNDER VEHICULAR LOADING

摘要

This paper presents some results on the dynamic responses of the world's first concrete-filled steel tube cable-stayed arch bridge under vehicular loading.The study is carried out based on a three-dimensional vehicle-bridge coupled model.A finite element model for the bridge is firstly built and validated using the field measurement data.The HS20-44 truck specified in the AASHTO(2004)specification is adopted for vehicle loading in the analysis and is simulated as a multi-degree-of-freedom vehicle model.The dynamic impact factors(IM)obtained from the responses of some key bridge components and the perceptible level of vibration of the bridge are studied.The results show that:(1)the impact factors of key structural components of the bridge studied are generally below the value of 0.33 specified in the AASHTO LRFD code;(2)pedestrians can feel “lightly hard to walk ” on the bridge when two trucks move side by side under poor road surface condition.