某飞鸟式拱桥拱座开裂加固后静动载试验与分析

针对某飞鸟式拱桥拱座加固后结构性能进行静动载试验。分析了静载试验中控制位置变形、应变,吊杆轴力等控制指标,观测了拱座裂缝变化情况。并采用模态分析法比较动载试验所确定桥面前两阶振型及频率,对实测加速度及动挠度变化规律与理论结果进行比较,计算确定冲击系数。试验结果分析表明,该桥检测指标均能满足要求,行车性能较好。表明该桥拱座加固效果良好,使用性能比较理想,可适应设计荷载等级的要求。

Static, Dynamic Load Tests and Analysis of Strengthened Cracked Arch Seat of a Flying Bird Type Arch Bridge

The static and dynamic load tests were made for structural performance of the strengthened arch seat of a flying bird type arch bridge.Several control indices formulated for the static load test,such as those of deformation and strain of the controlled positions and hanger axial forces,were analyzed and the changes of cracks in the arch seat were observed.The modal analysis method was used to compare the first two orders of vibration modes and frequency of deck of the bridge determined according to the dynamic load test and also to compare the changing laws and theoretic results of the measured acceleration and dynamic deflection,and the impacting coefficients were then calculated and determined.The analysis of test results indicates that all the indices of the bridge can meet the requirements,the performance of vehicle traveling of the bridge is good,which in turn proves that the effect of the strengthened arch seat is good,the serviceability of the arch seat is satisfactory and the arch seat can accommodate the requirements of designed load grades.