Abstract：Abstract：Cylindrical cavity expansion theory is a common method to analyze the soil’s stress and strain during the construction of static pressure piles and mixing piles and has reached some achievement. However, there are some deviations between experimental results and the theoretical results because soil damage, which is come from soil disturbance around the pile during pile construction, isn’t considered when cylindrical cavity expansion theory of the pile is deduced. To effectively play the cylindrical cavity expansion theory role in the guidance to the pile construction, a changing cohesion formula with soil damage parameter caused by construction is structured. Based on theory of continuum mechanics and boundary conditions, the soil damage factor in the formula can be ascertained and soil changing cohesion formula containing soil damage is obtained. These theory and formula provide the basis when squeezing effect around the pile is analyzed. Based on the cylindrical cavity expansion theory and soil damage, substitute the cohesion formula into cylindrical cavity expansion theory and the distribution of stress and radius of plastic zone around the pile during construction can be analyzed by solving differential equations of equilibrium. Computation results considering soil damage show plastic zone range around the pile is bigger and stress variation around the pile is slower than that of elastic method. The reasonability of the method in paper has been verified by comparing with the different results which is obtained by the theory in terms of non-considering soil damage and considering soil damage in this paper and the existing theory in other paper. The comparison results also show this paper method considering soil damage is a rational and effective way to deal with extrusion effect during the construction of static pressure piles and mixing piles and very suits for engineering practice. Analytical method considering soil damage this paper is helpful to research pile’s construction technology in the different soil and pile’s effect adopting fine analysis method.
2016, Vol. 37 
