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The purpose of this paper is to present a numerical model of coupled heat, moisture transfer and their effects on the porosity changes of soil during the freezing process. Coupling among heat, moisture, and mechanical deformations is solved based on finite element method. The equilibrium equations of freezing process are investigated based on segregation theory. The numerical model is applied to a 2D problem of a laboratory frost heave test. Numerical simulation reveals the porosity characters during the freezing process. The frost depths and deformations also the porosity in consideration of the orthotropic properties of frozen soil is discussed.

The Chinese Dynamic Penetration Test (DPT) was used following the 2008 Wenchuan earthquake to measure penetration resistances of gravels that liquefied and nearby gravels that did not. The test has many advantages, including simplicity, continuous data acquisition, and robust equipment that is easily transported by light vehicles and low cost. A probability formula, developed from logistic procedures, was proposed using the 47 compiled DPT data. The DPT could be a viable test for measurement of penetration resistance of gravels in other parts of the world beyond China.

For cement-soil pile composite subgrade under rigid foundation, a three-dimensional nonlinear finite element analysis is performed to analyse critical length-diameter ratio based on deformation, which is first introduced, according to replacement ratio, pile-soil modulus ratio and the modulus ratio of substratum and reinforced area. It is found that critical length-diameter ratio of cement-soil pile under rigid foundation mainly depends on replacement ratio, the impact of pile-soil modulus ratio and the modulus ratio of substratum and reinforced area is relatively little.