摘要
依托伯勒博克孜隧道工程,采用水压致裂法对隧址区局部的最大主应力大小和方向进行测试;利用最小二乘法求得地应力随深度的变化特征;通过三维数值模拟对隧址区地应力状态进行反演分析,并评价隧道开挖后的围岩稳定性。结果表明:隧址区地应力随深度增大呈近似线性增加趋势,实测隧道埋深375.4 m处最大水平主应力13.01 MPa,最小水平主应力8.86 MPa,平均最大水平主应力方向N7.1°W;三维数值模拟反演地应力状态符合实测地应力值及变化规律,隧道洞周范围内南北向主应力最大值13.07 MPa,东西向主应力最大值9.00 MPa,隧址区存在高地应力;在支护结构作用下,隧道开挖后围岩稳定性较好,无塑性贯通区,围岩竖向变形与水平变形值均较小。
Based on the Bolebokezi tunnel project,the size and direction of the maximum principal stress in the local area of the tunnel site were tested by hydraulic fracturing method.The variation characteristics of in-situ stress with depth were obtained with the least square method.The in-situ stressl state of the tunnel site was analyzed by 3D numerical simulation,and the stability of surrounding rock after tunnel excavation was evaluated.The result shows that,the in-situ stress in the tunnel site increases approximately linearly with the augmentation of depth.After surveyed,the maximum horizontal principal stress is 13.01 MPa,the minimum horizontal principal stress is 8.86 MPa,and the average maximum horizontal principal stress direction is N7.1°W at the buried depth of 375.4 m.The state of in-situ stress inversion by 3D numerical simulation conforms to the surveyed in-situ stress value and variation law.The maximum principal stress in the northsouth direction is 13.07 MPa,and the maximum principal stress in the east-west direction is 9.00 MPa,and there is high in-situ stress in the tunnel site.Under the action of supporting structure,the stability of surrounding rock is good after tunnel excavation,with no plastic penetration zone,and both vertical deformation and horizontal deformation of the surrounding rock are small.
作者
耿招
黄纲领
雷安平
GENG Zhao;HUANG Gangling;LEI Anping(China Highway Engineering Consulting Corporation,Beijing 100089,China)
出处
《路基工程》
2025年第3期225-231,共7页
Subgrade Engineering
关键词
地质复杂
水压致裂法
地应力反演
监控量测
变形控制
稳定性
complex geology
hydraulic fracturing method
in-situ stress inversion
monitoring measurement
deformation control
stability
