各因素对盾构进洞杯形冻结温度场影响数值模拟研究

A Numerical Simulation Study of the Effect of the Various Factors on the Temperature Field in the Cup-Shaped Frozen Wall for Shield Entry

基于天津站站盾构进洞水平冻结加固工程,采用实际工程的冻结设计参数建立三维数学模型,模拟分析了冻结管外壁温度、含水量、杯体冻结管间距、杯底冻结管间距、冻结管直径对冻结温度场的影响。通过模拟研究得出冻结管外壁温度、含水量及冻结管直径对杯形冻结温度场整体发展影响较大,在冻结设计中根据冻结工期、现场施工环境以及盐水温度发展规律进行合理设计;杯体冻结管间距对杯体冻结壁影响相对较大,对杯体冻结壁的交圈时间影响程度较大;杯底冻结管间距对杯底温度场发展影响较大。

With the horizontal freezing reinforcement project for shield entry at Tianjin Station as the engineering background,a 3-dimensional mathematical model is established in the light of the freezing parameters of the actual project,with the effects of the temperature of the external wall of the freezing pipe,the moisture content,the spacing of the freezing pipes of the cup body and the spacing of the freezing pipes at the bottom of the cup,and the diameter of the freezing pipe on the freezing temperature field simulated and analyzed. Through the simulation research,it is found that the temperature of the external wall of the freez-ing pipe, the moisture content and the diameter of the freezing pipe all have a relatively great effect on the entire development of the cup-shaped freezing temperature field. Thus,in the freezing design,it should be rationally designed according to the freezing duration,the construction surroundings of the site,and the developing law of the temperature of salty water. The spacing of the freezing pipes of the cup body has a relatively great effect on both the frozen wall of the cup body and the enclosing time of the frozen wall of the cup body. The spacing of the freezing pipes at the bottom of the cup body also has a relatively great effect on the development of the temperature field of the cup bottom.