Dynamic pressure prevention and control technology of coal mining face with shallow depth and contiguous seams passing through overburden goaf and coal pillars

According to dynamic pressure accident easily occurred when the fully mechanized coal mining face in shallow depth seam and contiguous seams group passed through goaf of the overburden strata and concentrated coal pillars and large area roof cutting and powered supports jammed accident occurred, in combination with the dynamic pressure prevention and control practices in the fully mechanized coal mining face in No.31 seam of Shigetai Mine, the paper analyzed the known min ing affected to the concentrated coal pillar lose stability in the goaf of the overburden strata and to cause the key block of the overburden base rock suddenly rotary and stability lost. Thus the articulation structure of the base rock key block in the low seam would be destroyed and the rotary stability lost would be changed to failure slidin g stability lost. The mine pressure bump load role from the stability lost of the key block in the top and low base rocks would directly cause the dynamic accident. In co mbination with the roof movement law, the centralized coal pillars blasting, mining face length reduction and other technology conducted in advance could avoid the bas e rock stability lost and bump overlied in the top and low seam and could reduce the overburden strata movement influence scope and degree. At the site, the micro-sei smic monitoring and measuring, multi point displacement gauge in the surface boreholes, surface ground subsidence observation and other means were applied to guid e and verify and could effectively solve the dynamic pressure accident easily occurred when the fully mechanized coal mining face in the shallow depth seam and contig uous seams passed through the goaf in the overburden strata and concentrated coal pillars.