Mechanism and Application of Strong Mine Pressure in the 40205 Working Face of Xiaozhuang Mine
In view of the problem of strong mine pressure behavior in large mining height working face,taking the 40205 working face of Xiaozhuang Coal Mine as the engineering background,a roof fracture structure model is constructed to analyze the mechanism of large mining height strong mine pressure behavior.The results show that the resistance of the support subjected to three compressions indicates that the number of basic roof layers is two or more,leading to periodic strength changes of the periodic weighting step distance and the presented magnitude of compressive strength.The maximum pressure value of the support reaches 12 000 kN,through caculation,the static load above the support is obtained to be 3160 N.The sliding instability of the key block is the fundamental reason for the strong mine pressure phenomenon in the 40205 large mining height working face.Comprehensive prevention and control measures such as online monitoring,process regulation and control,roof management,and support management are proposed,with a focus on omnibearing prevention and control when advancing to 200 m and 646 m.The comparison of microseismic events shows that the intensity of the three compressions shows an increasing trend,and the height of roof fracturing is developing upwards.After hydraulic fracturing,the periodic weighting step distance is shortened from 26.5 m to 19 m,which achieves good results and provides a reference for solving the problem of strong mine pressure behavior in similar mines.
large mining heightstrong mine pressure behaviorsupport resistancehydraulic fracturingprevention and control measure