High-precision measuring device and method for dynamic displacement of structural micro-crack

Abstract

The invention discloses a high-precision measuring device and method for dynamic displacement of a structural micro-crack. An arch-shaped elastic pedestal is disposed above a predicted cracking position of the micro-crack in a spanning manner, the arc-shaped inner wall and the arc-shaped outer wall of the top of the arch-shaped elastic pedestal are correspondingly provided with a first strain gauge and a second strain gauge in an attached manner, transverse dynamic displacement changes generated by opening and closing of micro cracks on the surface of the structure are converted into bending strain changes of the upper surface and the lower surface of the top of the arched elastic base, the first strain gauge and the second strain gauge serve as half-bridge resistors respectively and are electrically connected with the strain measurement module to form a half-bridge measurement circuit. the bending strain change of the first strain gauge and the second strain gauge is measured, namely the bending strain change of the top of the arched elastic base, and the end displacement change of the arched elastic base is determined based on the linear relation between the end displacement change of the arched elastic base and the bending strain change of the arched elastic base, namely the dynamic displacement change of the micro-crack is measured.

Description

technical field [0001] The invention relates to the technical field of anti-seismic engineering structures, in particular to a high-precision measuring device and method for the dynamic displacement of structural micro-cracks. Background technique [0002] The shaking table test is one of the direct and effective methods to study the seismic characteristics of actual civil engineering structures or hydraulic engineering structures. The damage characteristics of structures under earthquakes, especially the nonlinear characteristics of structural damage, are currently research difficulties and hotspots. The dynamic change process of the vibration damage of the model structure in the simulated earthquake of the shaking table, especially the displacement evolution process of the crack after the structure cracks, can effectively reveal the structure damage mechanism. Due to the relationship between the geometric scale of the model, the cracking change of the actual structure is ...

AI Technical Summary

Problems solved by technology

However, the strain gauge will fail after the microcracks in the model structure are generated, and a series of dynamic evolution processes such as subsequent evolution, expansion change, and opening and closing changes after the microcracks cannot continue to be measured.

It is precisely because it is very difficult to measure the dynamic changes of micro-crack displacement that the shaking table tests of most model structures have not monitored the key process after micro-crack cracking-and this process is the most critical and can reveal the nonlinearity of geotechnical structure models. The test process of the characteristics of the destruction process makes this kind of test data unable to fully reveal the structural damage characteristics, and also greatly reduces the test effect

This has also become a bottleneck in the study of model structure shaking table failure tests.

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