Abstract:
For the phenomenon of protective layer cracking and surrounding rock large deformation of auxiliary vertical shaft ingate in Yuanzigou Coal Mine, simulation analysis and field measurement method are used to analyze the reasons of deformation and failure of ingate. The results show that jointed muddy soft surrounding rock, superimposed stress caused by chamber group, additional stress from surrounding rock expansion which caused by fissure water and construction disturbance are the main causes of the deformation and failure of the auxiliary vertical shaft ingate. Based on the analysis of the stressed mechanism, we proposed the large section surrounding rock control technology. The overall repair scheme uses the organic combination of cable circular integration support, grouting combining with deep and shallow holes, locking shed leg at bottom and the counter-pulled anchor to strengthen the support of surrounding rock. Mine pressure observation results show that surrounding rock deformation is under effective control and the roadway size reaches the requirements.