Earth pressure analysis on limited soils between front wall and back wall of griddling underground diaphragm wall

Based on the limit equilibrium theory and the hypothesis of double planar sliding plane, earth pressure calculation models of front and back walls of the underground diaphragm wall are established with the consideration of cohesion and the width of limited soils. And formulae are also deduced to calculate the earth pressure of the front and back walls. According to these formulae calculation programs are compiled using Matlab software. The results of calculation examples show: At first, the earth pressure of both front wall and back wall are in between the Rankine´s active earth pressure and Rankine´s passive earth pressure. While the earth pressure of the front wall is less than the back. Secondly, the front wall earth pressure show the nature of ´active earth pressure´ while the behind wall earth pressure obviously show the nature of ´earth pressure at rest´ concerning the magnitude of the data. At last, the value of front wall earth pressure and back wall earth pressure is related to the width between front wall and behind wall, internal friction angle and cohesion of soils and calculation depth. However, the change of cohesion has little effect on both front wall earth pressure and back wall earth pressure.