Study On The Computation Method Of Passive Earth Pressure On The Pre-inclined Slope Of Pile-plate Wall

The empirical formula modified based on Coulomb earth pressure theory and Rankine earth pressure theory is widely used in the structural design of retaining engineering.Classical earth pressure theory and existing empirical formulas can not accurately solve the problem of passive earth pressure calculation in front of retaining wall.In view of this,this paper,relying on the construction science and technology project of Chongqing,carries out"study on the calculation method of passive earth pressure on inclined slope surface in front of pile-slab wall",and adopts the means of combining theoretical analysis,physical model test and numerical simulation test.When the soil is inclined down in front of the pile-slab wall,the passive earth pressure in front of the wall is obtained.The force is comprehensively analyzed.The main research contents and results are as follows:(1)Based on Rankine's classical earth pressure theory,the sloping slope fill in front of the wall is simplified to a horizontal fill with the height of overlying soil h,the determination method of h is given,and a simplified calculation method is derived.(2)Based on Coulomb's classical earth pressure theory,a calculation model of passive earth pressure on sloping slope in front of pile-slab wall is established,and a formula for calculating passive earth pressure is derived.The effects of slope inclination angle?,internal friction angle?of soil,depth of pile and plate wall H on sliding rupture angle?are analyzed,and the influence of friction angle?between retaining wall and fill soil?,and the equivalent of cohesive force c on horizontal lateral earth pressuree_z are also analyzed.(3)A self-made test model box was used to study the passive earth pressure with different inclination angles in RB displacement mode.The influence of inclined slope angle on the size,distribution and the position of the joint force of the passive earth pressure in front of the wall was analyzed.The surface of the test results shows that the horizontal lateral passive earth pressure exhibits a nonlinear distribution under the RBT displacement model,and the working point of the resultant force is lower than that of H/3.(4)Based on the physical model,the numerical calculation is carried out with PLAXIS software.It is found that when the displacement of pile-slab wall is RB mode,the passive limit equilibrium state can not be reached at the same time for the soil with different depths,and the rotational displacement of the lower soil is smaller than that of the upper soil.When the displacement of pile-slab wall is T mode,the displacement of soil with different depth reaches the state of passive limit equilibrium is basically the same.(5)The two theoretical formulas are compared with the physical model test and the numerical model test,and the applicable conditions of the two theoretical formulas are obtained.