Study On Interaction Mechanism Between Anti-slide Pile And Soil Based On Soil Arch Effect

China is a mountainous country with a wide range of mountainous areas.At the same time,due to the continuous expansion of the scope of engineering construction,it is inevitable to make appropriate changes to some areas with complicated geological and topographic conditions,among which,the number of induced landslides cannot be ignored.At present,anti-slide pile has been widely used in the treatment of landslide.For anti-slide pile and soil interaction mechanism,there have been many scholars have done a lot of theoretical analysis and practical research,also has obtained the rich research achievements,but because of the complexity of the pile-soil interaction,this research also is not very mature,has not been widely accepted.Anti-slide pile design to a large extent,still need a reference to similar engineering design,or with the engineering technical personnel's experience,this will inevitably brings to the application of anti-slide pile is not scientific and subjective sex from personnel of course of study,are more likely to have the serious landslide disaster caused by unreasonable design.Therefore,it is very necessary to further study the interaction between pile and soil and provide references for anti-slide pile engineering practice.Based on the above review,this paper adopts the method of combining the stress theory analysis of soil arch model,centrifugal model test and finite element numerical calculation.The main research and results are as follows:(1)the soil arch plane mechanics model was established,and the stress of soil between piles was simplified and calculated,and the control surface with the maximum stress at the section of the arch foot was obtained.Based on the failure theory of mohr-coulomb,the force calculation of arch foot section is carried out,and the calculation formula of reasonable pile spacing of anti-slide pile is derived.(2)according to the derived formula of pile spacing,discussed the parameters in the formula of landslide thrust q,cohesion c,internal friction Angle ?,pile side width of a and b on the influence of pile spacing,pile back widt.It is concluded that the pile spacing decreases with increasing of landslide thrust q,along with the soil shear strength parameters c,? cross section size of the pile and the increasing of a and b.(3)according to the data obtained from the centrifugal model test and the soil sliding condition after the test,it can be concluded that the soil pressure of piles with spacing of 4b,5b and 6b is distributed in a parabolic shape,while that of piles with spacing of 7b is in a trapezoid shape.4b,5b,6b of the soil arch effect is more obvious when the pile spacing,determined according to maximum bending moment of the pile body is 5.6b pile spacing is relatively ideal,but given a certain amount of safety stock,suggest appropriate to reduce the pile spacing to 4b~5b teams.(4)to establish the finite element calculation model for further analysis of the soil arch effect between piles,research: the soil arch effect with the pile section size,the parameters of shear strength of soil and the increase of surface roughness increased;Pile back width and cohesion of the effect of the soil arch effect is bigger,width,Angle of internal friction and pile side friction coefficient of the soil arch effect of the effect is relatively small,pile been pressure is parabolic,the soil arch effect along the depth direction was weakening trend,consistent with the analysis of the former chapters.(5)when the ratio of pile spacing to pile diameter is fixed,the increase of pile diameter cannot enhance the earth arch effect,so the adoption of larger pile diameter cannot be excessively pursued to obtain a good supporting effect.