Overburden failure and strata pressure behavior characteristics under condition of shallow coal seam in gully terrain
Zhao Jie
Liu Changyou
Li Jianwei
Abstract：Aimed at the fact that dynamic strata pressure accidents easily occurred during upward section mining of gully terrain at the No.4104 working face of Chuancaogedan Coal Mine,the breaking forms of the key strata and strata pressure characteristics during upward mining of the working face under the condition of non-existing key strata in gully region were studied.Results indicated that the key strata of the upward section existed as a "cantilever beam" mode under the effect of non-uniformly distributed load because of the lack of gully key strata,which may induce shear damage or tensile damage of the key strata rock mass,and correspondingly the instable forms presented as sliding instability or rotary instability which were influenced by the valley slope angle.In the condition of No.4104 working face,overlying key strata presented as tensile damage and rotary instability failure form when gully slope angle less than 57°,while key strata presented as shear damage and sliding instability failure form when gully slope angle more than 57°.Field test showed that dynamic strata pressure behavior was obvious during mining at upward section of gully terrain of the mining face.Finally,countermeasures to slow down mine pressure behavior and improve roof control effect were proposed.
Keywords：shallow buried coal seamgully upward section miningoverlying key stratumbreaking formstrata pressure behavior
Publication Date：2017-01-01
Pages：7( 34-40 )