Cross section measurement method for fiber volume fraction of steel fiber concrete

Abstract

The invention relates to a cross section measurement method for the fiber volume fraction of steel fiber concrete. The method comprises the following steps of: establishing a regression formula of the volume fraction of steel fibers and the number of the steel fibers on the cross section area of the steel fiber concrete, which is determined by a cross section method; collecting a test piece on site or manufacturing the test piece on site or indoors, and rupturing the test piece through a splitting test or a bending tensile test; measuring the number of the steel fibers on two cross sections, and taking the average value of the number of the steel fibers on the two cross sections as the number of the steel fibers on the cross section of the test piece; and substituting the measured number of the steel fibers into the regression formula to deduce the volume fraction of the steel fibers. By the method, the volume fraction can be tested at any position on a construction site, and the tested concrete can be non-poured concrete or cured concrete. The method contributes to the quality inspection of a steel fiber concrete mixture, is suitable for the quality accident reason analysis and project acceptance of the cured concrete, and is low in test cost, a test instrument is simple, and test flexibility is achieved.

Description

technical field [0001] The invention relates to a method for measuring the fiber volume ratio section of steel fiber concrete, which is suitable for the quality inspection of steel fiber concrete mixtures used in civil engineering, and can also be used for the analysis of the cause of steel fiber concrete structure quality accidents in civil engineering and the acceptance of projects Evaluation of steel fiber volume content. Background technique [0002] At present, the relevant codes of civil engineering stipulate that the water washing method is used to measure the volume ratio of steel fiber reinforced concrete during the construction process. The water washing method is to wash the mixed concrete with water and absorb the steel fibers with a magnet, then dry the steel fibers, weigh the dried mass and calculate the volume ratio. The water washing test requires a lot of water washing, and must be completed before the initial setting of the mixed concrete. Each sample need...

AI Technical Summary

Problems solved by technology

This method can be used for the indoor unhardened concrete mixture steel fiber concrete volume ratio test, it is not suitable for the determination of the volume ratio of the concrete pouring site, and it is also unable to measure the volume ratio of the steel fiber of the concrete that has been cured, and the test cost is high

[0003] Therefore, the water washing method has the disadvantages of long test time, small number of tests, and the test position is limited by water, drying and weighing. It is not suitable for the detection of the volume ratio of steel fiber in on-site concrete and the detection of the volume ratio of cured steel fiber concrete. In addition, the water washing method needs to provide electricity for drying, and the water consumption of the test is large. The sampling from the site needs to be transported to the laboratory, and the test cost is high.

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