斜拉桥索力测量的可靠度研究

Reliability Research of Stay Cable Force Measurement of Cable-Stayed Bridges

从概率分析的角度探讨频率法测量索力的精度。综合运用响应面-蒙特卡罗法,以及索力-频率对应关系的有限元及样条拟合方法,形成一种计算量少、计算精度高的频率法测量索力可靠度分析方法。该法可以考虑索结构参数和索实测频率变异性对频率法测量精度的影响。采用该法对广州珠江黄埔大桥北汊斜拉桥各施工阶段的索力测量进行可靠度分析,获得理想的结果,检验了方法的正确性与实用性,同时也为该桥索力测量提供概率意义下的精度信息。

The accuracy of cable force measurement by the frequency method is studied from the point of view of the probability analysis. By comprehensively using the response surface and Monte-Carlo method, the finite element method and the spline fitting technique for determination of the tension-frequency relation of cables, a reliability analysis method that features less calculation and high calculation accuracy for the stay cable force measurement by the frequency method is developed and the analysis method can take into account of the influence of variations of the cable structure parameters and measured frequency on the accuracy of the measurement. With the developed method, the reliability analysis of the cable force measurement at different construction stages of the north bridge （cable-stayed bridge） of Huangpu Bridge over Zhujiang River in Guang-zhou was conducted. The satisfactory results of the analysis were achieved, the correctness and practicability of the method was checked and at the same time, the accuracy information of probability significance was also provided for the cable force measurement of the Bridge.