Rock crack propagation simulation testing device and testing method

Abstract

The invention discloses a rock crack propagation simulation testing device and testing method. In the rock crack propagation simulation testing device, an extrusion head is fixedly connected to the lower surface of an upper pressure-bearing plate, a rock sample is arranged on the upper surface of a lower pressure-bearing plate, a groove is formed above the rock sample, the rock sample at the bottom of the groove is provided with a precrack, one end of an upper extrusion plate is fixedly connected with one end of a lower extrusion plate, a sliding wheel is hinged to the fixed joint of the upper extrusion plate and the lower extrusion plate, the outer surface of the rock sample is provided with an acoustic emission wave detector, the acoustic emission wave detector is connected with a computer through signals, and a loading end acts on the upper pressure-bearing plate and is connected with the computer through signals. The testing device has the advantages that the rock sample is easy to manufacture, simple in testing and low in testing cost; stable and controllable fracture loads can be applied according to stress conditions of the rock sample, so that the rock sample generates directional cracks, and relations between loads, loading speed and other factors and rock sample crack propagation can be accurately analyzed.

Description

technical field [0001] The invention relates to the technical field of rock mechanics tests, in particular to a rock crack propagation simulation test device and test method. Background technique [0002] The initiation and expansion of microcracks in rocks are the main mesomechanical factors affecting the macroscopic deformation and failure of rocks. Because there are many microcracks inside the rock, under the action of external force, stress concentration will be formed at the end of the microcracks, and the microcracks will begin to expand into tensile cracks and gradually connect through, eventually leading to the destruction of the rock. Therefore, pulling failure is one of the root causes of rock failure. The observation and study of rock crack propagation process is of great significance to the establishment of rock crack propagation model and constitutive relationship, the analysis of rock deformation and failure mechanism, and the stability evaluation of rock engi...

AI Technical Summary

Problems solved by technology

At present, the existing technology mostly uses the direct tension method or the Brazilian splitting method to study the growth of rock cracks. The direct tension method is difficult to make samples, and less

In the Brazilian disk splitting test process, because the test process is affected by various conditions, such as the stiffness and strength of the backing plate (strip) between the pressure plate and the Brazilian disc, the size and shape of the backing plate, etc., the results obtained Sometimes not enough information needed to analyze the problem can be obtained, or even the essence of the problem can not be reflected

[0003] The Chinese patent document with the publication number CN104819898A discloses a mining rock crack expansion test device and test method. The device uses water injection to pressurize the rock specimen to produce cracks, but it cannot test the expansion of rock cracks in dry or original state.

The Chinese patent document with the publication number CN105319138A discloses a device and method for rock fracturing tests. The device mainly applies a specific voltage to the fluid through a voltage applying device, so as to break down the fluid and fracture the rock sample. However, this method cannot accurately control the magnitude of the applied load in the process of fracturing rock samples, and it is difficult to observe the crack initiation and expansion process of rock cracks in detail.

The Chinese patent document with the notification number CN205209884U discloses a simple device for rock subcritical crack propagation experiments. The device mainly loads the "V"-shaped incision of the fracturing rock specimen through a rigid sphere. The control of the loading process cannot accurately analyze the relationship between the load, loading rate and other factors and the crack growth of the rock specimen, and it is difficult to manufacture the rock specimen with a "V"-shaped notch, and the test conditions are harsh, which is not conducive to reducing the test cost

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