高黎贡山隧道1#竖井（副井）突水淹井封堵施工技术

为解决高黎贡山隧道1#竖井（副井）掘砌时发生的高压突水淹井难题，根据地层特点和施工情况，分析突涌水原因； 类比其他行业深井淹井突水口封堵施工经验，提出水下混凝土直接封堵、静水压抛碴注浆封堵和改性水泥浆止水垫与注浆碎石堵水层相结合封堵3种方案并进行比选，选用在静水压状态下采用改性水泥浆止水垫与注浆碎石堵水层相结合封堵的方案，介绍其施工控制技术，并通过抽排水施工对封堵效果进行验证。结果表明： 1）改性水泥浆止水垫与注浆碎石堵水层相结合封堵方案中采取的改性水泥止浆垫参数设计、构筑止浆垫施工工艺、改性水泥浆的配比等施工技术能够满足深大竖井突水口封堵施工要求； 2）深水承压摄像头能够对施工过程进行有效监控，实施控制性排水能够准确检验封堵效果； 3）50 m厚改性水泥浆止水层能够达到封堵突水口的预期目的，完成后经抽水验证可知突水口封水率达99%，封堵效果较好。

Sealing Technology for Water Inrush of Vertical Shaft No. 1 (Auxiliary Shaft) of Gaoligongshan Tunnel

High pressure water inrush occurred to shaft No. 1 (auxiliary shaft) construction of Gaoligongshan Tunnel and the shaft was flooded. In this paper, the causes for the water inrush are analyzed based on strata characteristics and construction situation; and then 3 sealing schemes, i.e. underwater concrete sealing, grouting under hydrostatic pressure and combined sealing of modified cement slurry waterstop layer and grouting stone sealing layer, are proposed by comparing with shaft sealing experience of relevant industry; finally, the construction control technology is introduced, and the sealing effect is verified by pumping and drainage construction. The treatment results show that: (1) The sealing scheme that combined modified cement slurry waterstop layer and grouting stone sealing layer is selected; and the parameter design of modified cement slurry waterstop layer, the slurry waterstop layer construction technology and the cement slurry mixing proportion of the selected scheme can meet the sealing requirement of water inrush in deep and large vertical shaft. (2) The deepwater pressure camera can monitor the construction process effectively, and the sealing effect can be checked accurately by controlled water drainage. (3) The sealing effect of modified cement slurry waterstop layer with thickness of 50 m is good, reaching 99% sealing rate.