Residual strain based after-damage bearing capacity estimation method of concrete beam bridge

Abstract

The invention provides a residual strain based after-damage bearing capacity estimation method of a concrete beam bridge. The method is characterized in that the residual strain ep of concrete in a stressed area of the concrete beam bridge which does not meet the requirement by assessing in a static load test according to the concrete damage elasticity modulus Er in the stressed area; the real strain and stress state of a section can be obtained according to the section load balance and plane surface deformation; the standard extreme bearing bending moment Mjj and design bearing bending moment Mdc are obtained according to the actually-measured concrete strength and section size; the damage degree can be determined according to the concrete residual strain, and thus the actual extreme bearing bending moment Mzj and the bending moment Mzc for normal use can be obtained. With the adoption of the method, the technical problems that the assessment of the bearing capacity of an existing concrete beam bridge is highly influenced by subjective factors, only the bridge performance under test load is assessed in the traditional static load test, and the real working state and bearing capacity of the concrete beam bridge cannot be obtained, can be solved.

Description

technical field [0001] The invention relates to the technical field of engineering detection, in particular to a method for evaluating the bearing capacity of reinforced concrete beam bridges after damage based on residual strain. Background technique [0002] In the long-term service process, the bridge structure is affected by the external environment, vehicle loads, etc. In addition to bearing static loads, it also bears various fatigue loads, which inevitably produces structural damage, and the difference between the actual working state of the structure and the design state Also getting bigger and bigger. According to the statistics of the Ministry of Transport, there are nearly 100,000 bridges with potential safety hazards in my country's highway bridges, accounting for about 13% of all bridges. Under long-term overloading or unpredictable external forces, these bridges with potential safety hazards are prone to serious accidents. Therefore, the working state of rein...

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Problems solved by technology

[0007] The invention relates to a residual strain-based evaluation method for the bearing capacity of reinforced concrete girder bridges after damage. It aims to solve the problem that the evaluation of the bearing capacity of existing reinforced concrete girder bridges is greatly affected by subjective factors and that the traditional static load test can only evaluate the "test load". "Under the performance of the bridge, the technical problem that the real working state and bearing capacity of the reinforced concrete girder bridge cannot be obtained

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