Cement concrete self-restriction contraction stress test approach

Abstract

A concrete self-restriction shrinkage stress detecting method relates to a method for detecting the concrete self-restriction shrinkage stress. The method aims at solving the problem of generating the self-restriction shrinkage stress caused by the shrinkage deformation difference at various positions in a concrete sample that is not considered by the existing concrete shrinkage stress detecting method. The method is provided with a humidity sensor arranged in a preformed hole of a first concrete sample with a prism shape, embedded with a plurality of groups of metal gauge heads at the two ends of an axes of a long axis of a second concrete sample with a prism shape in advance, respectively embedded with a metal gauge head along two ends of an axis of a thin slice shape sample, respectively detects relative humidity value, shrinkage value, and completely free shrinkage and deformation value at the location with a distance of h from the surface of the concrete, thereby calculating the self-shrinkage capacity at the location with the distance of h from the surface of the concrete. The detecting method of the invention can accurately and conveniently detect the self-shrinkage capacity of the concrete generated by the shrinkage and deformation at different positions of the inner and outer layers under different environmental conditions.

Description

technical field [0001] The invention relates to a method for testing concrete self-constrained shrinkage stress. Background technique [0002] Concrete shrinkage produces tensile stress due to external constraints. When the tensile stress reaches a certain level, the concrete structure will crack. This is one of the main reasons for cracking and durability reduction in actual structural engineering. Concerning concrete shrinkage and the resulting restrained tensile stress, a lot of research has been done at home and abroad and many achievements have been made. As far as concrete shrinkage stress is concerned, there are mainly two types of evaluation and testing methods: one is to calculate the shrinkage stress value of concrete under different constraints by testing the shrinkage value and elastic modulus of concrete specimens; the other is to use uniaxial For the restrained concrete specimen, the shrinkage stress value of the concrete under the fully or partially restraine...

AI Technical Summary

Problems solved by technology

[0004] The purpose of the present invention is to provide a self-constrained shrinkage stress test method for cement concrete in order to solve the problem that the existing concrete shrinkage stress testing and evaluation methods do not take into account the shrinkage deformation differences at different positions in the concrete specimen

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