冷板冻结冻土温度场数值模拟与实测研究

Numerical Simulation and Experimental Study on Temperature Field of Frozen Soil with Cold Plate

针对盾构接收时洞门位置地下连续墙与地层交界面突发涌水的情况,采取留置盾壳、盾壳内敷环形冻结管形成冷板传递冷量的方式,对盾壳外侧地层进行冻结,形成环形冻结壁封堵导水通道。采用ANSYS软件对冷板冻结设计方案进行仿真模拟分析,研究冻结温度场变化规律及冻结壁温度分布特征。研究结果表明,仿真模拟与现场实测冻结壁的发展相近,冷板冻结可有效加强土层与盾壳交界面的冻结效果,提高施工安全水平,提升盾构进洞应急处置能力。

In view of the sudden water gushing at the shield tunnel hole interface between diaphragm wall and stratum when shield tunneling receives,it is proposed to freeze the stratum outside the shield shell to form a circular freezing wall to block the water flowing channels by means of retaining the shield shell and laying annular steel freezing tubes inside the shield shell to transfer cooling energy.ANSYS software is used to simulate the freezing design scheme of cold plate,the variation law of freezing temperature field and the temperature distribution characteristics of freezing wall in the form of cold plate are studied.The results show that the development of simulation and field measurement of freezing wall is similar,cold plate freezing can effectively strengthen the freezing effect of the interface between soil layer and shield shell,improve the construction safety level and enhance the emergency disposal ability of shield tunneling.