Study On Calculation Method For Responses Of Single Row Of Stabilizing Piles Embedded In Multiple Stable Layers

It is quite common that piles embedded in multiple layers in actual projects which adopt slide-resistant pile to reinforce slide slope or landslide.Current standards suggests adopting conversion method of ground coefficient area to calculate embedded segment of piles,but this method usually results in a mismatch between calculated results and reality.Based on the effects caused by the differences of different layers,it has important actual meanings to introduce a simplified calculation method of embedded multiple layers.This thesis studies single row of stabilizing piles embedded in multiple stable layers and takes internal force of embedded piles on different layer interfaces into consideration to conduct researches with theory analysis and numerical modeling method.Main research results are as the follows.(1)It concludes four analysis models of embedded multiple layers,namely,“whole rock type”,“soil-rock-rock type”,“soil-soil-rock type”,and “whole soil type”.Considering the continuity of internal force and transformation on interfaces of different layers,this thesis respectively deduces calculation formulas of slide-resistant piles' internal forces based on these four analysis models with focuses on three different constraint conditions of the bottom of piles.(2)It respectively conducts calculation case-analysis of “whole rock type”,“soil-soil-rock type”,“soil-rock-rock type”,and “whole soil type” applying the method of this thesis and methods suggested by standards,and compares analyzing results with results of numerical modeling.With calculation cases of “whole rock type”,“soil-soil-rock type”,“soil-rock-rock type”,and “whole soil type”,this thesis concludes the displacement of upper embedded piles,maximum bending moment,and maximum shearing force error are 26.8%?1.1%?-0.9%,-6.5%?8.2%?0.6%,-6.3%?7.5%?4.1%,-6.5%?8.2%?2.0%.Compared with standard method,this method is more related to results of numerical modeling.(3)It analyzes and compares calculation results of pile internal force and displacement when embedded ration is 1:2,1:2.5 and 1:3.Compared with ratio of 1:2,when ration is 1:2.5,the displacement of sliding parts in calculation cases,maximum bending moment of piles and shearing force of “whole rock type”,“soil-soil-rock type”,“soil-rock-rock type”,and “whole soil type” respectively increase 38.5%?-4.4%?40.8%?38.6%,72%?-5.7%?45.9%?104.9%,70.1%?-5.6%?68.9%?163.6%,25%?-5.1%?6.7%.The decrease of embedded ratio has the biggest influence on the slide-resistant pile's internal force and displacement of “soil-soil-rock type”,and it has the smallest influence on “whole rock type” and “soil-rock-rock type”.As for “whole soil type”,the decrease of embedded ratio has little influence on embedded segment's internal force when conversion depth exceeds 2.5.This thesis' s research results of calculation method on slide-resistant pile's internal force when embedded segments are on multiple layers might provide guidance and reference on projects of slide-resistant slide strengthened slide slope and landslide.The thesis has important theoretical meanings and application values.