基于统计矩理论的无模型结构损伤识别方法研究

Model-free structural damage identification method based on statistical moment theory

通过对统计矩理论的分析,提出了一种在时域内利用结构加速度八阶矩作为损伤指标,直接利用输出信号快速判断结构有无损伤及损伤位置的识别方法。通过对典型Benchmark四层钢框架结构数值仿真模型和实测试验进行分析,研究了不同位置斜撑缺失以及弹性模量减少工况下的损伤位置识别,并通过12层标准RC框架振动台试验数据分析了不同楼层梁的损伤工况,判定了各楼层相对损伤程度变化。结果表明:利用响应信号的结构加速度八阶矩适合作为损伤识别的直接判别指标,通过两次定期测试的相对变化可以直接快速对不同损伤工况进行损伤诊断。

One model-free structural damage direct identification method based on eighth acceleration statistical moment index in the time domain is proposed in this paper.One scenario analysis is performed on numerical simulation model and test model of the typical four-story steel Benchmark structure,considering the damaging cases of different positions of the missing braces and the reduced elastic modulus respectively,and the damaged locations are studied.Another scenario analysis is performed on the 12-story standard RC frame structure with different damaged floor beams,and the relative damage level of each floor is determined.The results show that the eighth acceleration statistical moment of structural acceleration response is suitable as a direct index for damage identification.During the relative change of the index within two tests,the damage identification of different damage cases can be directly and quickly diagnosed,which is significant for the preliminary rapid assessment.