A kind of gravity expansion force constant pressure loading coal rock creep test device and method

Abstract

The invention discloses a coal and rock creep test device and method for gravity expansion and constant pressure loading. A loading system, located above the triaxial pressure chamber, is used to adjust the mass of the overall weight required by the test requirements through the quality of the water, and to adjust the magnitude of the force exerted on the coal and rock specimens; the force expansion device is located in the The upper part of the triaxial pressure chamber is connected with the closed water tank gravity loading system, which is used to amplify the force exerted by the closed water tank gravity loading system and axially load the coal and rock samples in the triaxial pressure chamber . The invention is easy to operate and low in cost, provides stable test conditions for studying the creep properties of coal and rock under complex stress state, can accurately grasp the relevant data of the increase of the deformation of coal and rock with time under the action of constant load, and ensures the stability of coal and rock. The scientificity, accuracy and rigor of deformation and instability research.

Description

technical field [0001] The invention belongs to the technical field of coal mine experimental devices, and in particular relates to a gravity expansion force constant pressure loading coal rock creep test device and method. Background technique [0002] Creep damage is one of the main failure forms of rock, and many rock engineering problems are closely related to rock creep. The destruction of a project often has a time course. In other words it is controlled by the creep of the rock. Some researchers even pointed out that some basic issues of rock mechanics cannot be solved without considering the creep properties of rocks. In the process of coal mining, with the increase of mining time, the coal rock is subjected to different loads, resulting in different degrees of creep deformation, and its stability will be greatly affected. and destroyed. It can be seen that under the action of constant load, the deformation and instability of coal and rock are closely related to ...

AI Technical Summary

Problems solved by technology

The disadvantages of this technical solution: the constant load is applied through the counter force plate, loading spring, force sensor, and pressure plate, which has great limitations and cannot meet the force required by many test requirements; it cannot be accurately loaded with constant pressure, and it will be affected by the external environment. Larger errors due to changes

Insufficiency of this technical solution: Applying a constant load to the test piece by weights has great limitations and cannot meet the force required by many tests; it cannot be accurately loaded with constant pressure, which will cause large errors due to changes in the external environment, etc.

Insufficiency of this technical scheme: the constant load is applied to the loading system of the test piece through the reaction frame, loading system, controller and the interior of the reaction frame. Pressure loading; the grating and pressure sensor will have a large error, and accurate data cannot be obtained

Insufficiency of this technical solution: Although it is more automatic and precise to apply constant load by loading the motor and weight group, it cannot provide stable test conditions in time in case of power failure and other emergencies; Changes in weight due to changes in the external environment, etc.

Due to the limitation of the speed of manual observation and recording, it is difficult to record the output changes when the force of the sensor changes suddenly, so that some important information may be missed, or in case of a sudden power failure or leakage, etc. Unable to provide stable test conditions in time

At the same time, the creep test process is manually loaded by the experimenter, which has great limitations and cannot meet the force required by many test requirements, and the weight of the weight will change due to changes in the external environment.

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