针对神东矿区布尔台煤矿42煤层覆岩存在坚硬顶板，回采生产中采空区顶板大范围悬顶不垮落诱发的强矿压显现限制了矿井安全生产这一现状，通过理论分析以及现场工业试验，对坚硬顶板覆岩结构简化力学模型进行分析，分析了坚硬顶板悬顶受力特征及其对矿压显现的影响；进一步提出了对工作面顶板施工定向水力压裂措施来弱化坚硬顶板岩层，控制其垮落，揭示了水力压裂弱化坚硬顶板降低回采期间矿压显现的机理；结合42202工作面现场工程条件，确定了顶板坚硬岩层层位，并对水力压裂方案、参数进行优化设计，并在施工中监测水力裂缝扩展、水压及注水量变化，分析水力压裂技术对坚硬顶板岩层的控顶效果。综合研究结果表明：对42202工作面覆岩粉砂岩层施工水力压裂措施后，顶板岩层有效弱化，压裂卸压影响区域内工作面来压强度整体降低，尤其是来压峰值压力降幅明显，降低约10%；来压步距降低4%；来压前支架平均阻力降低2.6%；来压时支架平均阻力降低6.8%；动载系数降低4%；工作面煤壁片帮得到遏制；同时，辅运巷道两帮及顶底变形量分别减小100、30 mm；〖JP3〗辅运巷道浅部及深部围岩应力分别降低2.5、1 MPa，锚杆、锚索受力分别下降29、22 kN，反映出对坚硬顶板施工定向水力压裂能有效降低工作面矿压显现，避免形成强烈冲击，可满足安全生产要求。

In view of the existence of a hard roof in the overburden of No.42 coal seam in Burtai coal mine of Shendong mining area, the strong mine pressure behavior induced by large-scale over-hang of the roof in the gob and the non-collapse of the roof in the mining production limits the current situation of mine safety production, through theoretical analysis and field industrial test, the simplified mechanical model of hard roof overburden structure was analyzed, and the stress characteristics of suspended hard roof and its influence on mine pressure were analyzed. Further, the directional hydraulic fracturing measures were put forward to weaken the hard roof strata and control its collapse, revealing thta the mechanism of hydraulic fracturing weakening the hard roof and reducing the mine pressure behavior during the mining period; combined with the field engineering conditions of 42202 working face, the hard roof strata position was determined, the hydraulic fracturing scheme and parameters were optimized, the expansion of hydraulic fracture, the change of water pressure and water injection were monitored, and the roof control effect of hydraulic fracturing technology on the hard roof strata was analyzed. The comprehensive research results show that: after the hydraulic fracturing measures are applied to the overburden siltstone strata of 42202 working face, the roof strata are effectively weakened, the weighting strength of the working face in the area affected by fracturing pressure relief is reduced as a whole, especially the peak pressure of weighting is decreased by 10%, the weighting step distance is decreased by 4%, the average resistance of the support before weighting pressure is decreased by 2.6%, the average resistance of the support during weighting is decreased by 6.8%, and the dynamic load coefficient is decreased by 4%. At the same time, the deformation of the two sides and the top and bottom of the auxiliary transportation roadway are reduced by 100 mm and 30 mm respectively; the stress of the shallow and deep surrounding rock of the auxiliary transportation roadway is reduced by 2.5 MPa and 1 MPa respectively, and the stress of the anchor bolt and anchor cable is reduced by 29 kN and 22 kN respectively, which reflects that the directional hydraulic fracturing for the construction of the hard roof can effectively reduce the mine pressure behavior of the working face and avoid the formation of strong impact. It can meet the requirements of safety production.