A nonlinear structural damage identification method based on ARCH model

Abstract

The invention discloses a non-linear structure damage identification method based on an ARCH model, comprising the following steps: respectively collecting acceleration time history response of a multi-layer structure under a reference state and a state to be detected of each layer structure; The linear AR models of each layer structure in the benchmark state and the state to be detected are established respectively. Calculating a residual sequence of each layer structure in a reference state and a state to be detected respectively; According to the residual series, the benchmark ARCH model and the ARCH model to be tested for each layer are established respectively. According to the benchmark ARCH model, the benchmark conditional heteroskedasticity sequence of each layer structure is extracted by the ARCH model to be tested, and the conditional heteroskedasticity sequence to be tested is extracted by the ARCH model to be tested. Calculating a probabilistic conditional variance index PVCI according to a reference conditional heteroscedasticity sequence and a conditional heteroscedasticity sequence to be tested; The conditional heteroscedasticity conversion index ARCHCI was calculated according to PVCI index. Nonlinear structural damage identification is carried out according to ARCHCI index. The invention can improve the identification ability of the non-linear damage of the structure, can have high anti-interference performance, and thus improves the reliability of the identification.

Description

technical field [0001] The invention belongs to the technical field of structural damage identification, in particular to a method for identifying nonlinear damage of structures. Background technique [0002] Due to factors such as environmental impact, man-made damage, and the variation and degradation of material performance, engineering structures may suffer from various damages during service. Severe damage will cause the collapse or failure of the building, resulting in huge economic and human life losses. , so it is necessary to conduct identification research on structural damage. The damage identification method based on the time domain is one of the current research hotspots, which can directly use the time history data of the structural dynamic response for damage identification. Compared with the frequency domain method, the time domain method does not require time-frequency conversion of the signal, and directly uses the measurement signal to identify the damage...

AI Technical Summary

Problems solved by technology

[0005] Aiming at the deficiencies of the above-mentioned prior art, the present invention provides a nonlinear structural damage identification method based on the ARCH model, which solves the technical problem that the prior art cannot accurately ide

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