Mechanical models of support-surrounding rocks under different top coal conditions in fully-mechanized top-coal caving face

The study on mechanical model of support-surrounding rocks in fully-mechanized top-coal caving face is important to control the system stability of support-surrounding rocks, ensure safety production of face. The mechanical models of support-surrounding rocks in fully-mechanized top-coal caving face were built with the determination of support working resistance, movement rules of top-coal under different mechanical properties and the influence of top coal mechanical property on breakage angle of the immediate roof and top-coal. They were studied by using methods of in-situ measuring and statistical. The models were simulated on different top coals according to mechanical property by using elastic body, plastic and elastic body, and plastic body. It explains that the influence of top coal mechanical property on support working resistance, reflects that the influence of top coal mechanical property on the relation of support-surrounding rocks and stability. The models were applied to the numerical simulation on the influence of support construction on tip-to-face roof stability, determination of support working resistance under-different top coal conditions, and the control of the tip-to-face roof stability on the field.