Concrete hydrothermal curing and stress-strain integrated testing device and testing method thereof

Abstract

The invention discloses a concrete hydrothermal curing and stress-strain integrated testing device and method thereof, and relates to the technical field of civil engineering material testing. The integrated testing device is composed of a circulating water bath system, a mold system, a strain monitoring system, a stress-strain analysis and calculation program and the like. Whole-course automaticaccurate acquisition and analysis of internal stress and strain of concrete in the hydrothermal unsteady-state curing process are achieved, and traditional contact type circumferential strain acquisition is converted into non-contact type radial length change acquisition; the problems of data drift, low repetition rate of test results, interference of hydrothermal unsteady-state conditions on testequipment and a data acquisition process and the like caused by the adoption of an adhesive resistance type strain gauge are solved, and the device and method are suitable for real-time analysis andconcrete internal stress-strain evolution rule monitoring in a hydrothermal maintenance environment. The support is provided for the regulation and control of the concrete hydrothermal curing conditions and the performance optimization.

Description

technical field [0001] The invention belongs to the technical field of civil engineering material testing, and in particular relates to concrete hydrothermal curing and its stress-strain integration testing device and testing method. Background technique [0002] my country is currently in the golden period of high-speed railway construction. The use of steam-cured concrete prefabricated components, such as track slabs, sleeper rails and simply supported box girders, has greatly accelerated the pace of high-speed railway construction in my country, shortened the construction period, and has significant economic benefits. benefit. [0003] However, research in recent years has found that accelerated curing processes such as hydrothermal or steam will cause thermal damage to concrete (products), resulting in concrete (products) prone to swelling and deformation, coarsening of pore structure, and thermal embrittlement, etc. Quality defects will adversely affect the structural s...

AI Technical Summary

Problems solved by technology

However, in the above monitoring process, it was found that the resistance strain gauge was tightly attached to the steel ring with strong glue and epoxy resin, and there were signs of looseness in the gradually warming hot and humid environment, making the data unacceptable; at the same time, the resistance strain gauge Deformation occurs with the expansion of the steel ring, but after the steel ring cools down, the deformation of the strain gauge cannot be completely restored to before the test, so that if the above-mentioned in-situ strain gauge is still used for the next batch of concrete stress-strain with the same compatibility When the verification experiment is repeated, similar results are often not obtained, and even the results are quite different; if all the resistance strain gauges are replaced and re-pasted, this will bring errors in the positioning of artificial measuring points and the new strain gauge itself

In addition, the above two concrete shrinkage stress test methods have very large test mold sizes and different height-to-diameter ratios. Therefore, they are not suitable for the study of swelling and shrinkage stress of steam-cured concrete.

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