Study On Mechanical Characteristics And Improved Experiment Of Similar Soil Coal And Rock Mass

The physical properties, mechanical characteristics and improved experiment of coal mass in66207working face of Xinzhuangzi Coal Mine of Huainan Mining Group are studied systematically through laboratory experiment, numerical simulation, theoretical analysis and integrated research methods in the field. The theory of hydraulic bridge is applied to reveal the mechanism of water injection to improve the coal mass. Research shows that the coal seam in66207working face of Xinzhuangzi Coal Mine forms some physical characteristics similar to soil under the special geological and mechanical conditions over a long period. It is a dry, fragmented and loose mass which is similar to soil but not soil. The strength of soil and rock mass will increase with the increase of the pressure and decrease with the increase of particle size and proportion of coarse particles; its elastic modulus and poisson’s ratio will firstly increase, then decrease and finally have a tendency to increase with the increase of coarse particles. The improved technical scheme of2.5%water injection in similar soil coal and roak mass and conducting mining activities2days later are put forward contrast the improvement plan of water injection and grouting in similar soil coal and rock mass. The stability of coal and rock mass is the highest at this time. The influence of water injection in mechanics characteristics of coal and rock mass can be reasonably explained by using the theory of hydraulic bridge. Research results enrich the theory of coal and rock mass reinforcement, provide a theoretical basis for improving the stability of coal and rock mass and have a great significance with the implementation of coal mine safe and efficient production.