In-situ Stress Measurement and Analysis of Failure Mechanism of Surrounding Rocks at the Rasuwagadhi Hydropower Station in Nepal
(1 Institute of Crustal Dynamics, China Earthquake Administration, Beijing 100085; 2 No. 1 Branch of Sinohydro Bureau 7 Co., Ltd.,Meishan 620860; 3 Shanghai Investigation Design & Research Institute, Shanghai 200434)
Abstract：
A three-dimensional in-situ stress measurement by hydraulic fracturing was conducted at the Rasu?
wagadhi hydropower station in Nepal. The results show that the major principal stress at the field is 10.47 MPa with the azimuth of 18° and dip angle of 15° which are almost horizontal; the intermediate principal stress and the minor principle stress are 9.01 MPa and 6.34 MPa respectively, with the azimuths and dip angles of 158° and 71° and 285° and 12° respectively. The crustal stress field of the construction area is characterized by dominant tectonic stress with medium stress level. Based on the measured data, it studied the failure mechanism of surrounding rocks,with the results showing that the failure is of splitting pattern and the main reasons for this are a large angle between tunnel axis and principal stress, and medium and higher stress levels.
AO Linhai1 ZHU Kaibin2 GUO Qiliang1 PEI Xiaodong3 HOU Yanhe1
.In-situ Stress Measurement and Analysis of Failure Mechanism of Surrounding Rocks at the Rasuwagadhi Hydropower Station in Nepal[J] MODERN TUNNELLING TECHNOLOGY, 2019,V56(2): 44-49
2019, Vol. 56 