Nonlinear damage identification and experimental research#br#
based on ARCH model and residual metric
Zhang Feng1,2 Guo Huiyong1,2
1. School of Civil Engineering, Chongqing University, Chongqing 400045, China;
2. Key Laboratory of New Technology for Construction of Cities in Mountain Area, Chongqing University, Chongqing 400045, China
Abstract:To solve the problem of time-domain nonlinear damage identification of Three-dimensional steel frame structure, a damage identification method based on the residual metric index of the ARCH (Auto Regressive Conditional Heteroskedastic) model is proposed. Firstly, the basic principle is described, and the estimation methods of the order and parameters of ARCH model are given. Secondly, the characteristics of the structure’s nonlinear damage are analyzed. Considering that the traditional nonlinear identification index is difficult to be applied to the steel frame structure, the Euclidean distance index based on the ARCH model and the improved residual metric index are proposed to identify the damage location of the steel frame structure. Finally, the numerical simulation of an eight-storey shear structure is conducted to verify the effectiveness of the two damage indicators. And the proposed indexes are applied to the nonlinear damage identification of the transmission tower model. The simulation and experiment results show that the traditional nonlinear damage identification index is difficult to be directly applied to the steel frame structure damage identificationHowever, the proposed Euclidean metric index and residual metric index are sensitive and can be used to identify the nonlinear damage of the steel frame structure.