The Construnctiong Technology Research On Queershan Tunnel In The High Alpine And High Altitude Region

With the improvement of China's national economic level,the traffic network gradually extended and improved to the southwest.The southwest region has significant environmental and geological characteristics of high altitude and high cold.As an important part of the traffic network,tunnel engineering will be more and more constructed in the future.However,the special low temperature and hypoxia environment characteristics in the alpine and highaltitude areas will lead to problems such as reduced human function of construction workers,reduced construction mechanical efficiency,and slowed construction progress,which makes the traditional construction methods and organization and management techniques applicable to plain areas not applicable in the high-altitude areas.Meanwhile,the low ambient temperature will also lead to the decline of concrete construction quality in the tunnel,the tunnel safety and stability.Therefore,taking queerer mountain tunnel as an example,this paper foucses the key technical problems in tunnel construction with data investigation,theoretical analysis,field measurement and other methods.The main research results are as follows:(1)The average altitude of the tunnel is 4,200 m,the average annual temperature is 0.3 below zero,and the average annual snow day is 161 days.The tunnel is characterized by both high temperature and low oxygen.The tunnel site mainly passes through an adverse geological zone,which is formed by sand and boulders.At the same time,the tunnel area groundwater development,part of the femoral water.Based on the characteristics of environmental geology of the tunnel,the preferred construction method of the tunnel construction is given,which is the three-step and seven-step method of reserving core soil and three supplementary construction methods,which are the three-step and seven-step method,the three-step and middle-door method,and the four-step excavation method.(2)The construction scheme,technical control points and indexes of advanced geological prediction,advanced reinforcement and support,initial support construction,waterproof and drainage construction,secondary lining construction and monitoring and measurement are proposed respectively.(3)In view of the proposed construction method of Queershan tunnel,the construction organization design schemes of construction personnel,machinery and materials are formulated respectively,and the construction period guarantee measures are put forward,thus forming the construction organization technology of high-cold and high-altitude tunnel.