Study on effect of overlying strata stability during strip coal pillar excavation with paste backfilling
TANG Weijun
SUN Xikui
WANG Heng
SHI Xianyuan
LI Xiangyang
LI Yi
Abstract：According to stability problem of mining strip coal pillars with paste backfilling,based on engineering background of mining strip coal pillars under buildings in Xuchang Coal Mine,the overburden "activation" mechanism,laws of roof movement and influence factors of stability were studied by the method of theory analysis,numerical simulation and field measurement.The results showed that the cavity,fracture and rock mass structure in the goaf would evolve under the external force disturbance,and the rock support system of stope would be destroyed.The support of surrounding rock can be improved by controlling the strength of filling body,the filling rate,the stowing interval and the supporting strength.In the meantime,it demanded that early strength of the filling body must be greater than 0.13 MPa,and the later strength should be adjusted according to the change law of the width of filling body.The simulation results revealed that the peak value of overlying strata and surface subsidence curve was located in the central coal pillar area and the overlying strata was affected significantly by adjacent goaf.The 1 200 mm subsidence value reached the maximum at the center of working face.The strata behaviors was not obvious in process of mining strip coal pillars with paste backfilling and good effect in engineering application was obtained.
Keywords：paste backfillingstrip miningroof stabilityactivation of overlying strata
Publication Date：2017-01-01
Pages：7( 109-115 )