Multi-functional test-bed for load identification and damage identification of plate-girder structure

Abstract

The invention discloses a multi-functional test-bed for the load identification and damage identification of a plate-girder structure. The multi-functional test-bed comprises a T-type groove platform, a supporting device and a movable lifting stage; the supporting device comprises supporting upright columns; the bottoms of the supporting upright columns are installed on the T-type groove platform; four supporting upright columns are adopted; and the four supporting upright columns are distributed in two rows and two columns; the movable lifting stage is detachably installed on the T-type groove platform; and the top surface of the movable lifting stage is provided with an exciter A. The multi-functional test-bed of the invention can be applied to the load identification and damage identification research of a plate-girder structure test piece. With the multi-functional test-bed adopted, a foundation can be provided for the theoretical application research of structural dynamic characteristic parameter identification, structural optimization and the like.

Description

technical field [0001] The invention relates to the field of structural dynamics, in particular to a multifunctional test bench for plate girder structure load identification and damage identification. Background technique [0002] Structural load identification and damage identification belong to the second category of inverse problems in structural dynamics. [0003] Payload identification technology is also called payload reconstruction or payload deconvolution. It is a technology to reverse the dynamic load of the structure based on the known dynamic characteristics of the structure and the measured dynamic response. Load identification is used as an indirect method to calculate loads in harsh environments or loads that cannot be directly acquired by sensors. In order to solve the inverse identification problem, the structural model must be known. In most practical situations, the load identification problem is ill-conditioned because not all state variables or initia...

AI Technical Summary

Problems solved by technology

In practice, the identification method based on the frequency change ratio has shortcomings: the natural frequency is not very sensitive to the early damage of the structure, and sometimes it is difficult to obtain the correct identification result for the slight damage with stiffness damage less than 60%; In the low stress area of ​​the structure, damage identification cannot be performed by using the change of natural frequency; and the measurement frequency is not enough to provide sufficient information for damage identification, usually only the existence of damage can be determined, but the location and degree of damage cannot be determined

This type of method faces the following problems: the identification of mode shapes is easily polluted by noise, and the vibration mode changes caused by damage are often covered up by these test errors; the actual observation mode data is incomplete; although high-order mode shapes are more important to damage Sensitive, but difficult to measure accurately or even impossible to measure in actual engineering

[0010] According to literature research, there is currently no comprehensive test platform that can be used for load identification and damage identification of plate-girder structural specimens at the same time

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