基于改进Gauss-Newton法的在役桥梁结构参数识别

针对在役桥梁结构静力参数识别中识别参数初始值难以确定的特点,提出了改进Gauss-Newton法.先对在迭代矩阵中增加一个阻尼项以防止迭代矩阵出现奇异的方法进行初步识别,再将初步识别结果作为Gauss-Newton（G-N）法的初始值进行再识别,从而既克服了G-N法对初始值要求苛刻的缺点,又保持了G-N法识别精度高的优点.模拟试验结果表明,该方法既能有效处理奇异和非正定矩阵,消除由于初始估计值偏离真值过大而造成识别结果发散的困扰,又能大大提高识别精度,从而保证了在役桥梁结构参数识别结果的可靠性.

Parameter identification of existing bridge structure based on improved Gauss-Newton algorithm

It is difficult to assess the initial value when identifying the existing bridge structure parameters, so an improved Gauss-Newton method was put forward, in which the result of the improved Gauss-Newton algorithm is regarded as the initial value of Gauss-Newton algorithm. The precision of the identification will be improved by using this method. In order to validate the method, a numerical simulative test on a continuous beam with three spans was carried out. The results indicate that using the improved Gauss-Newton method, the singular iterative matrix and harsh terms of initial value of identified parameters can be overcome. The dependability of structure parameter identification can be guaranteed. 1 tab, 1 fig, 10 refs.