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通过两组钻孔应力解除法地应力实测和６ 组地应力Ｋａｉｓｅｒ效应测试， 查明了工程岩体内的空间应力状态为潜在走滑型， 其中σ１ 方向为Ｎ６６．９°～Ｎ８５°Ｗ， 它与水平面的夹角介于２０°～４０°之间， σ１ｍ ａｘ 为３５．３ＭＰａ。岩体应力场数值模拟结果进一步表明，研究区单斜层状各向异性岩层在自重应力和一定量级的ＮＷＷ向区域构造应力（８．９ ＭＰａ）共同作用下， 结果在隧道中部相对坚硬完整、弹模值较高的砂岩、粉砂岩、灰岩、部分砂质泥岩和软质岩层内的硬脆性夹层中形成了相对意义上的高地应力； 此外， 发育产状为Ｎ４０°～６０°Ｗ／ＮＥ∠６０°～８５°的次级断裂构造（ＥＳＲ测年值为５５×１０４ ａ）两侧１０～２０ｍ 距离以外地段， 由于其后期张扭性构造活动， 也普遍存在着可以导致岩爆发生的局部高地应力现象。岩爆类型划分研究中， 首先根据高地应力的成因， 将岩爆类型划分为自重应力型、构造应力型、变异应力型和综合应力型四大类； 然后依据具体应力条件， 并结合岩爆特征等内容， 再将岩爆划分成８个亚类。岩爆烈度分级研究中， 突出了现场容易判别的岩爆标志， 主要依据岩爆声响、运动特征、岩块形态特征、断口特征、发生部位、时效特征、影响深度以及对工
Through two groups of stress measurement of drilling stress relieving method and six sets of Kaiser effect test of ground stress, it is found that the spatial stress state in engineering rock mass is potential strike-slip type, where σ1 direction is N66.9 ° ~ N85 ° W, The angle between it and the horizontal plane is between 20 ° ~ 40 ° and σ1m ax is 35.3MPa. The result of numerical simulation of rock mass stress field further shows that the monolayer anisotropic rock strata in the study area are under the joint action of self-weight stress and a certain magnitude NWW tectonic stress (8.9 MPa) , High elastic modulus of the sandstone, siltstone, limestone, part of the sandy mudstone and soft rock within the hard and brittle interlayer formed a relatively high ground stress; In addition, the development of production for the N40 ° ~ 60 ° W / NE ∠ 60 ° ~ 85 ° sub-fault structure (ESR dating 55 × 104 a) on both sides of the 10 ~ 20m away from the segment, due to its post-tensile tectonic activity, there is also widespread can lead to rock burst Occurred local high stress phenomenon. According to the cause of the high ground stress, the rockburst types are divided into four categories: self-weighting stress, tectonic stressing, variation stressing and comprehensive stressing. According to the specific stress conditions and the combination of the characteristics of rockburst And other content, then the rock burst is divided into eight sub-categories. In the study of rockburst intensity grading, the rockburst marks that are easy to distinguish on site are highlighted, mainly based on the rock burst sound, movement characteristics, rock block morphology, fracture characteristics, occurrence site, aging characteristics, depth of influence,