公格尔水电站发电洞高温段关键施工技术

Key Construction Technologies of the High-temperature Tunnel for the Kongur Hydropower Station

布仑口-公格尔水电站地处昆仑山腹地,在强烈的构造运动作用下致使引水发电洞前段存在高地温现象,局部岩温达100℃,给工程施工带来了巨大的困难和挑战。结合工程特点通过室内外试验等手段从施工降温、爆破安全和支护技术等三方面对高温隧洞关键施工技术进行了系统研究。在充分利用当地自然条件(年平均气温0.9℃)的基础上,提出了"以通风为主并辅以低温冷水的综合降温技术",以极经济的代价解决了洞内高温问题;根据相关试验结果对作业面炮孔温度进行分区,有针对性的提出了相应的安全爆破技术;针对不同洞段情况提出了以喷砼替代二次衬砌、以预制混凝土替代模筑混凝土等支护技术。以上各项施工技术在本工程的成功实施,确保了该引水隧洞的顺利施工(于2012年5月5日贯通),并期望能为同类工程的施工提供参考和借鉴。

Bunlunkou-kongur hydropower station locates at the central land of Kunlun Mountains. Due to the strong tectonism movement,there are high-temperature problems in the forepart of the diversion tunnel where the temperature is more than 100 ℃ and brings tremendous difficulties and challenges to construction. The critical construction technology of high-temperature was analyzed from the fallowing respects: temperature-lowering measure,blasting safety and supporting technology. First of all,by taking full advantages of local natural conditions(the annual mean temperature is about 0. 9 ℃),an economical temperature-lowering measure is proposed which is mainly on ventilation and assisted by low cold water. Then,the blasthole temperature of the tunnel face is divided into three stages based on the correlating test results and put forward a corresponding blasting safety technology. Finally,a series of supporting technologies are proposed for different parts of the tunnel,i.e. replace secondary lining with shotcrete,and replace poured concrete with precast concrete. All of the technologies above-mentioned ensure the successful construction of the high-temperature tunnel. It is also hoped that the technologies can providing reference for solving the similar problems.