Analysis Of Cemented Soil Penetrative Performance And Its Permeability Influence On Stability Of Retaining Wall

The cementd soil has gaining wide popularity and broad application prospects in theseepage projects for its low-price, easy-obtaining and high-impermeability. As a concern,engineering damages, which include surface uneven settlement, piping, quicksand, andsubsurface erosion, caused by underground water are usually expericened during the practicalexcavation project. At the same time, underground water, permeability coefficient of thecement soil, and thickness of the retaining wall are considered having certain effect on thecapacity, permeability and stability of foundation pit. Therefore, the study of permeability ofcemented soil and stability of foundation pit were expacted to provide significant theoriticaland practical value into the career. During the first phase of this reasearch, the effects ofmaintaining time and cement content to the cemented soil permeability coefficient wereanalyzed. In the second phase, the software-ABAQUS was used to provide a numericalsumulation of the foundation pit, and performen a series calcultion regarding to the effect ofunderground water. A step-by-step process of this research work were listed as below:(1) The cemented soil specimens were casted with different cement content-7%,10%,15%. For each type of the specimens, maintainence duration various from7days,15days,30days,60days to90days.(2) The penetration test was conducted on cemented soil specimens with differentmaintainence duration. The influence of cement content and maintaining time on the cementedsoil permeability coefficient was analyzed. The power foundation fitting curve, whichrepresents the change of cemented soil permeability coefficient with various of cement andmaintaining time was obtained by linear regression.(3) The influence of groundwater seepage to foundation pit was simulated by ABAQUS.The capacity, dispalcement, and seepage of foundation pit was then analyzed with thesimulated model. The influence of different permeability coefficient and time effect tofoundation pit was discussed.(4) Stability against overturning, stability against sliding, pressure, and pore waterpressure of foundation pit was analyzed with different thincness of cemented soil retainingwall. The slope stability of foundation pit was analyzed by strength reduction method. Position of the sliding surface was determined by the displacement increment method.