Quantitative evaluation method for analyzing concrete workability based on bottom resistance, and device

Abstract

The invention relates to a quantitative evaluation method for analyzing concrete workability based on bottom resistance, and a device. The quantitative evaluation method comprises the following stepsof: (1) carrying out a fresh concrete bottom resistance test; (2) drawing a curve that the displacement and speed of a resistance test piece change along with time; and (3) quantitatively evaluating the concrete workability based on the bottom resistance condition. The device comprises a transparent plastic box, a resistance test piece, a sliding guide rail and a laser displacement sensor. By adopting the quantitative evaluation method and the device, the time and the displacement of the resistance test piece inserted into the concrete bottom can be accurately measured; then, the insertion speed is calculated, the curve that the displacement and the speed change along with time is drawn, and the sinking condition of the fresh concrete aggregate is quantitatively characterized through utilizing a concrete workability comprehensive coefficient, so that the quantitative evaluation of the concrete workability is realized, and the defect that the concrete segregation degree is difficult toquantitatively characterize by adopting a traditional method is overcome.

Description

technical field [0001] The invention relates to a civil engineering experiment method and device, in particular to a quantitative evaluation method and device for analyzing concrete workability based on bottom resistance. Background technique [0002] In civil engineering construction, in order to obtain a dense and uniform concrete structure and facilitate construction operations (mixing, transportation, pouring, vibration, etc.), fresh concrete must have good construction performance, which is called the workability of concrete. Fresh concrete has typical poor workability phenomena such as delamination, segregation and bleeding. The construction quality of concrete is the key basis of project quality, so the workability evaluation of concrete is particularly important for project quality and project safety. [0003] The connotation of workability of concrete mixture is relatively complicated, and it is difficult to fully and properly express it with a simple measurement m...

AI Technical Summary

Problems solved by technology

However, the conditions for measuring the rheological properties of concrete by concrete rheometer are relatively harsh. The expensive price and huge equipment volume of concrete rheometer limit its application range to the laboratory, and it is difficult to carry out economical and rapid testing on the construction site.

Therefore, at the construction site, the cohesion and water retention of fresh concrete are basically evaluated by visual inspection and construction experience. The current visual inspection method is not accurate, and the test results often fluctuate greatly depending on the difference between the testers.

[0004] Concrete with poor cohesion is prone to bleeding and segregation, which usually occur at the same time. Once the concrete bleeds, the water and mud float up, and the sinking stones are tightly bonded to the base, which will greatly increase Resistance inserted into concrete bottom

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