Study of Static and Dynamic Load Tests of Qingfeng Bridge in Ningbo

The Qingfeng Bridge in Ningbo is a steel and concrete hybrid girder self-anchored suspension bridge having a main span of 280 m.To judge the actual load-carrying capacity,evaluate the working performance under the designed service load,predict the operation conditions and also to provide the technical bases for maintenance and management of the bridge,the static and dynamic load tests were made for the bridge.The deflection of the main girder,displacement of the tower tops,cable force increment of the suspenders,tensile force increment of the strands of the main cables and sectional stress of the main girder and towers under different static load cases were measured and analyzed.In the dynamic load tests,the natural vibration characteristics of the bridge structure and the excited vibration of vehicle traveling were measured and the impact effect of the structure under the exciting action of vehicle traveling was analyzed.The results of the tests and analysis reveal that the force conditions of the structure are rational,the structure has good stiffness and strength,the dynamic performance of the structure is good and the structure can satisfy the design requirements.