Structural damage identification method based on ridge estimation and L curve method

Abstract

The invention discloses a structural damage identification method based on ridge estimation and an L curve method. The structural damage identification method comprises the steps of firstly, building a structural damage equation based on sensitivity of modal strain energy according to the sensitivity of the structural modal strain energy, then determining a basic estimation criterion of the ridge estimation according to the principle of Tikhonov regularization, then utilizing the L curve method for determining the optimal ridge parameter of the ridge estimation, working out the basic solution of the structural damage equation on the basis of the optimal ridge parameter, and finally correcting the result, so that the damage coefficient of a damage unit is obtained, and the structural damage is identified. According to the structural damage identification method based on the ridge estimation and the L curve method, by the adoption of the ridge estimation, the influence of an ill-conditioned problem on damage identification can be greatly reduced, the quasi-optimal ridge parameter is determined by the adoption of the L curve method, meanwhile, a correcting strategy for the ridge estimation is provided, and therefore the better damage estimation value is obtained.

Description

technical field [0001] The invention relates to structural damage identification, in particular to a structural damage identification method based on ridge estimation and L-curve method, which belongs to the structural damage detection technology. Background technique [0002] After the engineering structure is put into use, due to the effect of the environment, various damages often occur. Severe damage to the structure will cause the collapse or failure of the building, resulting in huge economic losses and personnel safety. Therefore, the identification of structural damage has always been a research hotspot in the world. It is more effective to use the change of dynamic characteristics before and after the damage to establish the corresponding damage equation, so as to solve the damage coefficient. According to the damage coefficient, the damage degree of the structure can be judged. However, in engineering practice, the test data will inevitably be disturbed by measur...

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Problems solved by technology

[0004] 1) It is difficult to solve the ill-conditioned damage problem by directly inverting the strain energy sensitivity damage equation;

[0005] 2) When the simple truncated singular value decomposition algorithm is used to deal with the problem of strain energy sensitivity damage equation, it is difficult to determine the appropriate truncation error, which easily leads to the problem of poor recognition accuracy

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