Test method for accurately measuring uniaxial tensile strength of rock

Abstract

The invention discloses a test method for accurately measuring the uniaxial tensile strength of a rock. The method comprises the following steps of 1, making a plurality of known uniaxial tensile strength rocks into hollow cylindrical test pieces; 2, placing the hollow cylindrical test pieces on a universal testing machine, carrying out a tensile test and recording a tensile force when the test pieces are broken; 3, taking the tensile force as an abscissa and taking the uniaxial tensile strength of the rock as an ordinate, and drawing a tensile force-tensile strength curve graph; 4, manufacturing the hollow cylindrical test pieces of the rocks to be tested; 5, carrying out operation which is the same with the operation in the step2; and 6, using a graphing method to find the uniaxial tensile strength of the rock corresponding to the tensile force. The method has the following advantages that 1, the traditional mode of testing rock mechanical parameters through directly stretching the cylindrical test pieces can be cleverly converted into the mode of stretching the hollow cylindrical test pieces, and an experiment is easy to implement; 2, through one-to-one correspondence, the uniaxial tensile strength of the test pieces can be known according to the measured tensile force; and 3, there is no special requirements to the samples, and the complexity of making the samples is reduced.

Description

technical field [0001] The invention belongs to the field of rock mechanics, in particular to a test method for measuring the uniaxial tensile strength of rock. Background technique [0002] The tensile strength of the rock refers to the ability of the rock specimen to resist tensile stress under the action of external load, which is the ratio of the ultimate load of the rock specimen to the tensile cross-sectional area when it is damaged by tension. Rock materials are often encountered in engineering construction, and its mechanical performance index of tensile strength is an important basis for design, inspection, control and quality evaluation. Tensile strength is one of the important mechanical properties of rock, and it is also a controlling parameter for safety and stability analysis in rock structure design. One of the more remarkable characteristics of rock materials is that their tensile strength is much smaller than their compressive strength and much smaller than...

AI Technical Summary

Problems solved by technology

[0014] However, the experimental conditions of the Brazilian test are very different from the conditions of rock failure under tension, and the results are also very different from those of direct traditional stretching. Therefore, the reliability of the test results of the Brazilian test has been questioned by the academic community.

In addition, the dispersion of the Brazilian test is very large, and it is not applicable to the test with small repeatability.

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