Experiment research of drain technology of tunnel in forever frozen soil
WANG Xing-hua,WANG Jian (School of Civil Engineering and Architecture, Central South University, Changsha 410075, China)
The Kunlunshan Tunnel is the longest high altitude permafrost tunnel in the Qinghai-Tibet Railway, also the longest altiplano railway in the world. The design of drainage system of the tunnel in permafrost area is the key to be referred to safety working of the tunnel. If the best amount of outflow of the tunnel could not be calculated correctly according to practical condition of tunnel, it could not be able to design a effect drainage system for the tunnel. It is maybe to decrease the working life of the tunnel and increase working fee of the tunnel. The basic designing principle of the drainage system of the permafrost tunnel was discussed in detail in the paper. And the test data got from the tunnel were simply analyzed. The distributing of temperature and water pressure drop in and out water proof layer in the tunnel was analyzed. Finally the basic rough estimating principle of the biggest flow quantity from the tunnel was putted up.