中文摘要：

在中国西南某新型引水式水电站工程中使用水压致裂技术开展了原地应力及相关岩体力学参数测试。结果表明,工程区现今应力场状态以NNW向挤压为主,最大主应力值为7.35～8.16 MPa,方向约为N33～52°W,倾角约26～39°。气垫调压室三维原地应力状态的最大主应力值为10.63 MPa,最小主应力为4.98 MPa;围岩岩体抗劈裂强度高值区在5.50 MPa以上,低值区为3.00～3.50 MPa。根据围岩应力分布非均匀性遵循的一般性规律,结合原地应力测量与裂隙围岩原地承载能力测试结果的各自特点,提出了利用地应力测量数据、原地承载力测试结果、弹性模量数据综合评估承压洞室围岩最小主应力的方法,给出气垫式调压室部位最小主应力综合评估值2.86 MPa。并分析了地应力状态对地下厂房、引水隧洞、气垫调压室稳定性的影响。

英文摘要：

The hydraulic fracture technology is employed to estimate the in-situ stresses and other relevant mechanical parameters of rock mass at a new-type diversion hydroelectric project in China.The measured results show that the engineering area is under the stresses with the orientation of NNW,and the maximum principal stress is from 7.35 to 8.16 MPa in magnitude,with the direction of N33°～52°W and the inclination of 26° to 29°.The maximum principal stress around the air-cushion pressure adjustment cavern is 10.63 MPa,and the minimum principal stress is 4.98 MPa;the high values of anti-cracking strength of wall rock mass are above 5.50 MPa,and the low values are between 3.00 and 3.50 MPa.According to the general law of stress nonhomogeneity in the wall rockmass,and considering the respective characteristics of measured in-situ stresses and anti-cracking strengths of fissures in wall rockmass,a new method is put forward to estimate the minimum principal stress in the wall rockmass,which incorporates the in-situ stress measurements,in-situ bearing capacity measurements,and elastic modulus data.By use of the new method,the estimated minimum principal stress is 2.86 MPa for the area around the air-cushion pressure adjustment cavern.Finally,the impacts of in-situ stresses on the underground factory caverns,water tunnels and air-cushion pressure adjustment cavern are discussed.