Study on Energy Dissipation and Damage Characteristics of Coal-rock Structural Body under Cyclic Loading

Abstract

In order to study the energy evolution and damage deformation characteristics of coal-rock structureal body, the energy dissipation ratio was introduced, and the uniaxial cyclic loading tests of coal-rock structureal body with different coal-rock height ratio were carried out to explore the energy dissipation characteristics during cyclic loading. The damage variables calculated by dissipative energy method and acoustic emission method were compared and analyzed, a joint calculation method of the damage variables was proposed, and then the damage and deformation evolution characteristics of the structureal body were discussed. The test results show that with the increase of strain, the energy dissipation ratio decreases and then increases. At the same strain level, the greater the coal-rock height ratio, the greater the energy dissipation ratio. When the coal-rock structureal body produces the same energy dissipation ratio, the greater the coal-rock height ratio, the greater the strain of the structureal body. The damage variable evolution law obtained by the joint calculation method is highly consistent with the actual deterioration process of the structureal body, and can more effectively reflect the development and propagation of cracks and fissures under load.

Keywords

• cyclic load
• coal-rock composite structure
• energy dissipation
• damage characteristics
• acoustic emission