Dynamic response law and influencing factors of roadway roof under mining-induced seismicity

MIAO Xiaodong; SU Shijie; CAI Shaoyang; GOU Leiyu; AN Dong; ZHENG Jianwei

doi:10.11799/ce202602012

Abstract：To reveal the dynamic response characteristics of a roadway roof under mining-induced seismicity,a simplified dynamic response model of the strata-support system under impact disturbance was established to study the dynamic response of rock strata at different positions under various conditions.The influence of impact disturbance,segmented rock layers,and changes in stiffness at different positions on the dynamic response of rock strata under conventional support was analyzed.The variations in rock strata dynamic response when using energy-dissipating support and after changes in damping were also discussed.The results show that the peak displacement of the rock strata response is proportional to the square root of the disturbance energy and linearly related to the initial velocity of the top layer.After subdividing the fine sandstone block above the coal seam into 7 segments,the peak displacement responses of m1 and ms decreased by 32.3%and 34.0%,respectively.Increasing ki to 5 times and ks to 25 times the original values reduced the peak displacements of m1,ms,and m7 by 60.5%,68.4%,and 81.1%,respectively.Using an energy-dissipating support with cs=212.5×105 N/(m·s-1)and increasing ci to 5 times the original value shortened the dynamic response time of the rock strata to 1.35 s.Therefore,reasonably modifying the rock strata structure,increasing support stiffness,and adopting energy-dissipating support can effectively reduce the dynamic response of rock strata induced by mining seismicity and enhance strata stability.