Regional Detection of Broken Surrounding Rock in Gateway Driving Along Goaf and Application

Abstract：The YTJ20 strata detection recorder was applied to the broken region detection of the surrounding rock in the gateway driving along the goaf.Based on the detection results,the gateway support suspension theory was applied to the evaluation and the rational study on the original support pattern of the gateway.There were three gateway cross sections selected in the excavated sections of the non through gateway.There were five measuring points selected in each cross section.The strata detection recorder was applied to the borehole camera detection of each measuring point.With the observation of the broken process and the statistics of the detection result,the broken region drawing was made.The analysis and detection results showed that the roof bedding crack was separate,the development was high and the compact coal of the coal wall in the goaf was broken seriously.The detection results could be applied to correct the original support parameters of the gateway.The length of the bolt was reduced by 200 mm,a bolt and steel mesh support was canceled to the support of the compact coal side.The mine pressure monitoring and measuring showed that the support effect was excellent.