摘要
Abstract
The diversion tunnel of Qireha Starr Hydropower Station is a long deeply buried tunnel,for which the complicated geological problems,such as high ground stress,rock burst,high ground temperature,etc.,occur during the construction,which have larger impacts on the tunnel surrounding rock stability,construction safety,tunnel supporting load and lining type.Through the methods of the in situ surrounding rock deformation and ground stress release testing,the numerical simulation back analysis and the experimental study on the lining time,etc.,the formation mechanism of high ground stress and rock burst,rock burst characteristics and failure mode as well as the causation of high ground temperature of the long deeply buried tunnel are analyzed,while the impacts from the high ground stress,rock burst and high ground temperature on the construction,the lining load and lining type are also studied.For the tunnel section through the surrounding rock with high ground stress,the high ground stress is relieved by means of the mode of time-lag during the initial supporting after the excavation.For the tunnel section with rock burst,the initiative prevention measures and strong construction supporting are made for ensuring the construction safety,so as to decrease both the possibility of rock burst and its hazard to the lowest extent.For the excavation of the tunnel section with high ground temperature,the cooling measures of ventilation,placing ice blocks at the working face and the mouth of venttube,spraying water on the working face and the nearby rock body,etc.are adopted,moreover,the designs of both the primary and secondary linings of the tunnel are improved and optimized as well.All these measures mentioned above ensure the safeties of the construction and operation of the diversion tunnel,and then have certain reference significances for both the design and the construction of the tunnel under the similar geological condition.关键词
高地应力/岩爆/高地温/深埋隧洞/关键技术/应对措施Key words
high ground stress/rock burst/high ground temperature/deeply buried tunnel/key technology/countermeasures分类
水利科学
