不同地连墙插入深度下承压含水层减压降水对既有隧道的影响_郑刚.pdfVIP

35 2 Vol.35 Supp.2 2014 10 Rock and Soil Mechanics Oct. 2014 (2014)2 0412 11 1, 2 1, 2 3 3 1. 300072 2. 300072 3. 300074 TU 921 A Influence of pressure-relief of confined aquifer on existing tunnel under conditions of different inserted lengths of diaphragm wall 1, 2 1, 2 3 3 ZHENG Gang , WANG Qi , DENG Xu , LIU Qing-chen (1. Key Laboratory of Coast Civil Structure Safety of Ministry of Education, Tianjin University, Tianjin 300072, China; 2. School of Civil Engineering, Tianjin University, Tianjin 300072, China; 3. Tianjin Architecture Design Institute, Tianjin 300074, China) Abstract: If the confined aquifer is not completely cut off by the diaphragm wall during the pressure-relief process which is used for preventing the heave failure of deep excavation, the sphere of influence of ground settlement caused by pressure-relief of confined aquifer is much larger than that caused by the excavation. Therefore, the deformation characteristics of the existing shield tunnels caused by pressure-relief of confined aquifer are simulated by finite element method; and then the diaphragm wall is inserted into the confined aquifer, the effect of the length of diaphragm wall into the confined aquifer on the deformation of tunnel is analyzed. The results show that, as the length of diaphragm wall inserted into the confined aquifer increases, the settlement of tunnel decreases. But because of the deformation of wall, horizontal movement of the tunnel is considerable during the pressure-relief process. So it should be poin