Study on rock pressure law and control technology under multi-layer hard roof in fully-mechanized top coal caving face
Zhu Zhijie
Wang Hongkai
Zhang Hongwei
Tang Guoshui
Lan Tianwei
Gao Ming
Abstract：Geological conditions of thick coal seam and multi-layer hard roof tend to result in the hydraulic support being crushed and rib spalling at the working face,as well as serious deformation of surrounding rock of the gob-side roadway together with dramatic strata behavior.The focus was laid on the fully-mechanized top coal caving mining face at Tongxin Mine,where the stress and deformation of surrounding rocks under the influence of multi-layer hard roof were monitored and analyzed.The results show that the mining stress generated by mining face has a large influence range.Under the impact of multi-layer overlying hard roof,the large overburden structure is formed,and the stress and deformation of the surrounding rock are "abruptly ascending" and "abruptly descending",alternately.The synergy of the large coal mining space and the multi-layer hard roof are the main reason for the serious deformation in the fully-mechanized top coal caving face.The control technology of energy dissipation and bracing with constant resistance and large deformation of anchor in hard and long-stay tunnel with hard pre-fracturing blasting is proposed,which can effectively prevent and control the strong mining pressure.
Keywords：extra-thick seammulti-layer hard roofstrata behavioroverburden large structure
Publication Date：2017-01-01
Pages：6( 1-6 )