Research For Long-Span Steel Truss Arch Bridge Load Test

Arch bridge is an early bridge-type which has a long history in the development of human history.Arch has a span,easy installation,beautiful appearance characteristics.This type of bridge is very common in modern society.Represented by a bridge load test detection technology in bridge construction as an important part, which plays an important role in the development of bridge construction.Load test provide scientific conclusions about bridge structure performance and construction quality for the assessment and verification of existing bridges.Load test also provide valuable data and experience for the future construction of more complex bridges.This dissertation first briefly describes the history and the main forms of arch bridges and then describes several steel truss arch bridges which is similar with Wanzhou Yangtzs River Bridge.Through the finite element model,we can get the structural response of the bridge structure under static and dynamic conditions and then detecting the value of real bridge.By comparing with the theoretical value,we can make scientific evaluation of the bridge about safety.In the case of static loads,we consider14different conditions,including abdominal oblique rod near the top of4#Pier,side cross-L/2near the top chord and side cross-L/2near the quarter pole and so on.Test stress for each cross-section and deflection for side cross and up chord of main cross.Test results showed that Wanzhou Yangtzs River Bridge has good stiffness and strength conditions.Selected the same semi-span with static test for dynamic test.Conditions were selected near the bottom chord side cross-L2.a main span of L/2chord.a main span3#short boom and the main span across the bridge.Consist of three experiments:pulse test.road test and brake test.Accord the dynamic strain.acceleration,displacement,natural frequency.damping ratio,deflection,derailment coefficient test,we conclude that Wanzhou Yangtsz River Bridge has a good dynamic performance.