渗流条件下滨海地层人工冻结多场耦合理论模型

Multi-field coupling theoretical model for artificial freezing of coastal soils under seepage

采用Navier-Stokes方程考虑流体动量守恒对渗流过程的影响,建立了考虑渗流对滨海砂土地层人工冻结过程影响的水-盐-热-力学理论模型。理论模型的计算结果与试验吻合良好,验证了所提模型的准确性。通过参数分析,探讨了渗流速度对冰、盐空间分布的影响。研究发现,渗流削弱了冻结效果,随着渗流速度从0 m/d增加到10 m/d,冻结管左右两侧的土体位移降低了23.1%;冻结管左右两侧的结冰范围缩减了37.8%;冻结管左右两侧的盐分的析出范围缩减了42.7%;砂层上游的吸附盐突变位置向下游移动了52%,下游的吸附盐突变位置向下游移动了32%。

A hydro-salt-thermal-mechanical theoretical model for the influences of seepage flow on the artificial freezing process in sand-clay stratum is derived.The influence of momentum conservation of fluid during seepage process is considered by using the Navier-Stokes equation.The good agreement between the results from the theoretical model and laboratory tests in the literature verifies the accuracy of the proposed model.The parametric studies are conducted to investigate the influences of the seepage velocities on the spatial distributions of ice and salinity.It is found that the seepage weakens the freezing effects.With the seepage velocity increases from 0 to 10 m/d,at the left and right sides of the freezing pipe,the soil displacement decreases by 23.1%.The range of water freezing is reduced by 37.8%.The range of salt precipitation is reduced by 42.7%.The mutation position of the adsorbed salt in the upstream of the sand stratum moves by 52%downstream,and that in the downstream moves downstream by 32%.