连续梁结构损伤识别的改进柔度阵方法

IMPROVED FLEXIBILITY MATRIX METHOD FOR DAMAGE IDENTIFICATION OF MULTI-SPAN BEAMS

传统柔度阵方法难以指示多跨连续梁这样一些复杂连续体结构在支撑处的损伤,提出以结构柔度阵某些自由度对应的对角元素的变化率作为损伤指示函数,对多跨连续梁结构进行更为有效的损伤识别。识别的机理是利用损伤指示函数对于单元损伤因子灵敏度矩阵的对角占优特性,产生对损伤因子分布的“覆盖效应”,从而反映出结构损伤的状态特征。文中给出有关计算公式,进行了数值模拟并比较几种状态的损伤识别结果,显示了本文方法的合理性。

A damage identification method for multi-span beam structures was proposed in this paper. The conventional damage indicator methods such as flexibility matrix method have difficulty in dealing with the damage identification of complex continuum structure such as multi-span beams. The present method takes the change rates of certain diagonal elements of the structural flexibility matrix as identification indicator function. The blanketing effect of the identification indicator function with respect to the damage factors makes it easy to identify the damage of multi-span beam structures. Some useful formulas were derived and the sensitivity matrix of the indicator function was studied. A numerical simulation is performed and the identification results of several damage status were compared. The results show that the present indicator function method is very simple and effective. It is especially suitable for the damage identification of the multi-span beam structures such as bridges.