Roof deformation patterns and key influencing factors in fully mechanized mining faces with paste filling

YANG Shifan; CHENG Zhirong; TIAN Ying; GU Ke; HE Lihui; ZHU Xuan

doi:10.11799/ce202511001

Abstract：To investigate the effect of the paste filling body on the roof and the influence laws of different factors on roof subsidence in paste filling working faces,w take the fully mechanized paste filling working face of Weisang Coal Mine as an engineering case.Using a combined research approach of theoretical analysis,numerical simulation,and field measurement,the spatial interaction relationship between the roof and the filling body is studied.The influence of face length(140～200 m),mining height(1.5～3.0 m),filling body strength(2.0～3.5 MPa),and filling rate(80%～95%)on roof subsidence is investigated,the influence laws of different factors on roof subsidence are analyzed,and the key influencing factors are determined.The weights of each factor are determined using the range analysis method and adjusted according to practical conditions.Theoretical analysis indicates when the roof initially contacts the filling body at the start of mining,the roof span is 1.82 m.As the working face continuously advances,the contact area between the roof and the filling body increases,and the roof subsidence value tends to reach its maximum of 0.333 m.Increases in face length and mining height cause an increase in the maximum roof subsidence value,with increments of 11.8%and 101.9%,respectively.Increases in filling body strength and filling rate cause a decrease in the maximum roof subsidence value,with reductions of 29.1%and 22.7%,respectively.The range analysis method yields the influence weight of each factor:mining height is the key influencing factor,accounting for 49.7%of the weight.The secondary influencing factors are filling body strength,filling rate,and face length,accounting for 22.8%,16.2%,and 11.3%of the weight,respectively.