Study On Reasonable Pile Spacing Of Fully-Embedded Anti-Slide Pile

In recent years,the fully-embedded anti-slide pile has attracted people’s attention in the landslide control and support engineer which is often used in practical construction.However,the design concept of anti-slide pile has not formed a comprehensive system,and lack of standardized theoretical basis until now.During the construction,designers often rely on the industrial standards and project experience to judge the pile spacing.As a result,it often generates great waste and hidden dangers.Therefore,selection of the spacing of anti-slide piles is worthy of scientific study.This article will focus on the study of reasonable value of spacing of the fully-embedded anti-slide pile.This paper has adopted indoor anti-slide pile model test and FLAC3D numerical analysis software to deduct the design formulas of pile spacing in practical engineering,and to study on the mechanical behavior of three kinds of pile spacing.In this paper,2,3,and 5 times pile spacing have been selected for comparative analysis,and the optimal pile spacing is obtained from 2 to 3 times pile spacing.Main works and conclusions are as follows:(1)With a lot of preliminary researches,based on the existing simplified calculation model of soil arch between piles,the transfer coefficient method is used to identify the distributed pressure before and after pile via the unit thickness soil arch.As the leading edge soil of the arch section was in three-direction stressed state,we established the strength condition of the mid-span section,joining with the static balance condition and the strength of mid-span section and the arch section to determine the pile spacing and check the practical calculation data.We now obtain the optimal value is in the range of 2 to 3 times the pile spacing.(2)The model test of anti-slide pile chamber was carried out to analysis the earth pressure before and after the anti-slope piles of different pile spacing and the stress distribution of the pile,meanwhile to monitor the displacement of the pile top.It is concluded that with the same sectional and horizontal force load,displacement of the pile turns out 2 times < 3 times < 5 times,and the anti-slide effect of piles turns out 5 times < 3 Times <2 times.(3)The FLAC3D numerical analysis software was used to make the modeling calculation to the application of anti-slide piles with different pile spacing in the slope.Then the numerical calculation results were strictly compared with the analysis results of indoor model test,and the approximately rules were obtained.