Environmental excitation data multiple-test-based Bayesian model correction method

Abstract

The present invention provides an environmental excitation data multiple-test-based Bayesian model correction method. The invention aims to eliminate the defects of a traditional method. With the method adopted, data obtained by multiple tests can be directly processed and analyzed; modal parameters obtained by the tests can be inputted by one step, and a model correction result is directly outputted. The method provided by the technical schemes of the invention can be used for solving the correction problem of actual test data-based finite element model. The method of the invention is divided into two stages. In the first stage, the acceleration data of a structure under environmental excitation which are acquired by the multiple tests are analyzed, so that the natural frequency and vibration mode of the structure which are measured by each test can be obtained; and the nondeterminacy of the modal parameters is calculated, and the modal parameters are represented by a covariance matrix. In the second stage, the optimal values of the model parameters of the finite element model requiring to be corrected are obtained through optimizing an objective function and based on the modal data parameters of the structure which are obtained based on the multiple tests and the covariance matrix thereof as well as the objective function built according to the Bayesian theory.

Description

technical field [0001] The invention relates to a structure finite element model correction technology. Background technique [0002] When doing structural design in the civil engineering field, a finite element model is usually established. After the structure is built based on the design drawings, some natural mode parameters of the structure include natural frequencies, damping ratios, mode shapes, etc. and are calculated based on finite element modeling. There is a clear difference in the results. Model correction technology is to correct the finite element model based on the structural modal parameters identified by the measured data, so as to obtain a more accurate finite element model, which will serve the subsequent structural health monitoring and damage identification. [0003] The existing technology has the following two problems: [0004] The first problem is that in the actual vibration test process, the number of sensors is often less than the number of meas...

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Problems solved by technology

[0008] The technical scheme of the present invention can be used to solve the problem of finite element model correction based on actual test data

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