Fluid Dynamics Based Numerical Analysis on Failure and Large Deformation of Soft Foundation

提出了一种基于流体力学框架的软土地基从初始状态到大变形和最终破坏状态的力学行为数值模拟方法。首先，提出了SIMPLE-VOF方法。在数值分析中，引入了具有屈服应力准则的Bingham本构模型。该方法再现了液化引起的侧向扩散的相似规律。在同一框架下，还再现了湖堤的大侧向流动破坏。其次，提出了基于CIP的可同时处理压缩流体和非压缩流体的数值方法。数值方法中还引入了Bingham模型。对于单层地基的横向铺展，可以再现相似定律。对存在非液化层的液化层的横向流动进行了预测。找到了在多层地面上定量再现实验结果的数值方法。最后，将CIP方法应用于加筋路堤的沉降预测分析。用新方法预测了加固对降低路堤沉降的显著效果。

A new numerical method was proposed to simulate the mechanical behavior of soft foundation from its initial condition to large deformation and ultimate failure state based on the fluid dynamics based framework.Firstly, the SIMPLE-VOF method was proposed. In the numerical analysis, the Bingham constitutive model which has yield stress criteria was introduced. The proposed method reproduced the similitude law on the lateral spreading due to liquefaction. The large lateral flow failure of the embankment in the lake was also reproduced in the same framework.Secondly, CIP based numerical method which can treat compressive and incompressive fluids simultaneouly was proposed. The Bingham model was also introduced into the numerical method. The similitude law was reproduced for the lateral spreading of single layer ground. The lateral flow of the liquefied layer on which non-liquefied layer exists was also predicted. The numerical method was found to reproduce the experimental results on multi layer ground quantitatively.Finally, CIP method was applied to predict the settlement analysis of the embankment with reinforcement. The significant effect of the reinforcement to reduce the embankment settlement was predicted by the newly proposed method.