超高地温条件下引水隧洞施工关键技术探讨

娘拥水电站引水隧洞全长15 406 m,马蹄型断面。在1#支洞及该支洞下游主洞开挖过程中遭遇了高地温围岩,最高岩体温度高达86℃,高地温段洞室长度长达400 m。基于高地温隧洞施工实践,从降低洞内环境温度、钻爆开挖控制、初期支护措施等关键因素着手对高地温隧洞施工关键技术进行了探讨。

Discussion on key technologies for construction of water diversion tunnel under super-high ground temperature

The total length of the diversion tunnel of Niangyong Hydropower Station is 15 406 m with a horse-shoe section. During the excavation of the No.1adit and its main downstream tunnel， the surrounding rock with a super-high ground temperature is encountered； of which the maximum rock temperature is as high as 86 ℃ and the length of the tunnel section with the high ground temperature is up to 400 m. Based on the tunneling practice under high ground temperature， the key technologies for the tunneling under high ground temperature are discussed herein from the aspects of the key factors such as lowering the environmental temperature inside of the tunnel， control of the drilling-blasting excavation， the initial supporting measures， etc.