深埋特厚煤层开采后高位坚硬顶板失稳造成强矿压现象突显，严重威胁矿井安全生产。为探究新型卸压防冲方案，以新巨龙煤矿8302工作面为研究背景，提出了高位巷与运输巷联合爆破卸压防冲方案。通过理论分析、物理模拟和数值计算相结合的方法，分析了高位巷爆破与运输巷爆破协同卸压原理，揭示了高位巷爆破卸压对于坚硬顶板的破断失稳机制，明确了高位巷爆破对于煤层应力场演化特征。针对现场工况条件，设计并实践了高位巷与运输巷联合爆破卸压及监测方案，取得了显著的卸压效果。结果表明：① 高位巷与运输巷联合卸压，弱化了覆岩结构，使其产生大量裂隙，破坏了其连续性，降低了覆岩承载能力。② 高位巷爆破使高位关键岩层初次垮落步距由144 m减小为84 m，周期垮落步距由24～30 m减小为12～24 m。煤层垂直应力由18.1～18.3 MPa减小至16.2～18.0 MPa，最大降幅11.47%，改善了工作面应力分布状况。③ 设计了8302工作面运输巷与高位巷联合爆破卸压方案。并从运输巷表面变形、覆岩应力、顶板深部位移等方面制定了监测方案。④ 现场工程实践表明：10⁴ J及以上的微震能量事件降幅64.3%，微震事件由改性前的“低频高能”逐渐向改性后的“高频低能”转化。联合爆破卸压后，围岩变形、钻孔应力及锚杆索受力对断层及不规则采空区具有高度的敏感性，而在进入正常阶段后，围岩稳定性得到改善，联合爆破卸压效果显著。为解决大采高坚硬顶板引发的强矿压显现问题提供了理论依据及实践参考。

The instability of high hard roof after deep-buried and extra-thick coal seam mining causes the phenomenon of strong ground pressure to stand out, which seriously threatens mine safety production. In order to explore a new scheme of pressure relief and scour prevention, taking 8302 working face of Xinjulong Coal Mine as the research background, a scheme of pressure relief and scour prevention by combined blasting of high roadway and gateway was put forward. By combining theoretical analysis, physical simulation and numerical calculation, this paper analyzes the principle of cooperative pressure relief of high roadway blasting and gateway blasting, reveals the fracture instability mechanism of high roadway blasting pressure relief on hard roof, and clarifies the evolution characteristics of high roadway blasting on coal seam stress field. According to the field working conditions, the pressure relief and monitoring scheme of combined blasting of high roadway and gateway is designed and practiced, and remarkable pressure relief effect is obtained. The conclusions are as follows: ① The joint pressure relief of high roadway and gateway weakens the overlying strata structure, causing a large number of cracks, destroying its continuity and reducing the bearing capacity of overlying strata.② Blasting in high roadway reduces the initial caving step of high key strata from 144 m to 84 m, and the periodic caving step from 24～30 m to 12～24 m. The vertical stress of coal seam decreased from 18.1～18.3 MPa to 16.2～18.0 MPa, with the largest decrease of 11.47%, which improved the stress distribution of working face. ③ The pressure relief scheme of combined blasting along the gateway and high roadway in 8302 working face is designed. The monitoring scheme is made from the aspects of surface deformation, overlying rock stress and deep displacement of roof.④ The field engineering practice shows that the microseismic energy events of 10⁴ J and above decreased by 64.3%, and the microseismic events gradually changed from "low frequency and high energy" before modification to “high frequency and low energy” after modification. After pressure relief by combined blasting, the deformation of surrounding rock, borehole stress and stress of anchor cable are highly sensitive to faults and irregular mined-out areas, but after entering the normal stage, the stability of surrounding rock is improved, and the pressure relief effect by combined blasting is remarkable. It provides theoretical basis and practical reference for solving the problem of strong ground pressure behavior caused by hard roof with large mining height.