硅酸盐通报2017，Vol.36Issue(1)：325-332,8.
天池坪隧道水压致裂法地应力测量及三维地应力场宏观扩展分析
Geo-stress Measurement by Hydraulic Fracturing Method and 3-D FE Regression Analysis of Multivariate Geo-stress Field of Tianchiping Tunnel
摘要
Abstract
Tianchiping tunnel is a very long single track tunnel from Lanzhou to Guangyuan of Lanyu railway, which is located at Tanchang couty of Gansu province. The total length of the tunnel is 14. 528 km. In the exploration area, a total of 26 hydrofracturing tests in 4 vertical exploration boreholes drilled from the ground surface are carried out. The results suggest that the present stress field of Tianchiping tunnel is dominated by horizontal stress, and the maximum horizontal stress is dominantly oriented NNW-NW-NWW. Stress magnitude is extreme high stress level. At the same time, the maximum horizontal stress orientations are closely consistent with those in the general contemporary stress field in southeast of Gansu Province. The maximum horizontal stress orientations in measurement hole No. LY1 is N40° W-N45°W. The angle is large between the maximum horizontal stress orientations and those along tunnel axis, which is a great disadvantage to the tunnel stability. Based on the geological conditions and rock mass properties, a 3D mechanical model is established, and the regional geo-stress field of tunnel area is analyzed by 3D multivariate FE regression from limited stress data of in-situ geo-stress measurement. The results of macro geo-stress field indicate that the transverse stress values are lager than 10 MPa along the tunnel axis,the lateral pressure coefficients is between 1 and 2,and stress concentration due to topography and other factors on local areas results to a great large lateral pressure coefficients. The results of macro geo-stress field are very important for dynamic design and construction.关键词
隧道工程/天池坪隧道/水压致裂法/地应力测量/回归分析/有限元Key words
tunnel engineering/Tianchiping tunnel/hydraulic fracturing method/geo-stress measurement/regression analysis/FEM分类
交通工程引用本文复制引用
余云燕,李国良,陈志敏,赵德安,尹建民,李永松..天池坪隧道水压致裂法地应力测量及三维地应力场宏观扩展分析[J].硅酸盐通报,2017,36(1):325-332,8.基金项目
国家自然科学基金(51268031) （51268031）
铁道部科技开发计划项目(2009G009B4) （2009G009B4）
甘肃省基础研究创新群体(145RJIA332) （145RJIA332）
