Structural finite element model modifying method based on displacement time history area under vehicle load

Abstract

The invention discloses a structural finite element model modifying method based on displacement time history area under vehicle load. According to the method, objective functions based on the displacement response time history area are in one-to-one correspondence with local rigidity of a structure, and accordingly, the local rigidity and boundary conditions can be selected as modifying parameters, the objective functions and modifying variables are definite in meaning, improvement in computing efficiency is benefited and convergence is easy. The method does not require bridge traffic interruption and extraction of dynamic characteristics of the structure (namely, time-frequency transformation), thereby being capable of avoiding shortcomings of existing methods.

Description

technical field [0001] The invention relates to a finite element model correction method, in particular to a structure finite element model correction method based on displacement time history area under vehicle load. Background technique [0002] With the rapid development of new materials and construction technology, my country's achievements in bridge construction have attracted worldwide attention. The rapid development of finite element software has enabled fine simulation of long-span and complex bridge structures, and special loads (earthquake load, impact load, impact Load, explosion load, etc.) structural response prediction becomes possible, a more accurate finite element model has the following advantages: (1) can quantitatively evaluate the structure; (2) provide the basis for accurate analysis of the structure (fatigue analysis, etc.); (3) Predict the response of the structure; (4) Provide a basis for structure control. [0003] However, when performing finite el...

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Problems solved by technology

[0005] (1) The finite element model correction method based on static response needs to interrupt bridge traffic, which is difficult to do in actual operation

[0006] (2) The finite element model correction method based on vibration characteristics needs to use Fourier transform to convert time-domain vibration data into frequency-domain data, which will generate time-frequency conversion errors, which will affect the accuracy of model correction;

[0007] (3) Since the actual excitation size and form of the bridge are unknown, in the process of extracting the dynamic characteristics of the bridge, it is usually assumed that the environmental excitation (vehicles, wind, ground fluctuations) satisfies the ideal distribution of white noise, but due to the complexity of the actual excitation , often this assumption cannot be established, resulting in errors between the identification value and the real value of the dynamic characteristic parameters, which in turn affects the accuracy of model correction

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