Study On Model Test Of Reinforced Three-Dimensional Slope With Stabilizing Pile

Reinforcement of three-dimensional slope is a very important issue on the basis of its stability analysis in slope engineering.In the crest load on slope,the stability of the slope has a significant space effect,and instability of the soil slope shows obvious three-dimensional feature because of the influence of the surrounding soil.The reinforcements in slope will enhance three-dimensional effect.This paper takes the partial crest loaded three-dimensional slope as the research object,with the method of model test,further study on the failure mechanism and instability mechanism of the three-dimensional slopes with different shapes,and analysis of slip surface features.At the same time,compared with the three-dimensional slope reinforcement model test,study the failure mechanism and characteristics of slip surface of the slope reinforcement,and analysis slope shape and the influence rules of the reinforcement.Test result is of great significance to clarify the three-dimensional slope instability and the reinforcement mechanism.The main research contents are as follows:A model test is performed to make a detailed research on the failure mechanism and features of slope sliding surfaces of partial crest load three-dimensional slope using model test.Designing an angle of 45 for slope of test model,considering the effects of slope shape(convex,concave slope),through the top loading plate,trigger instability and failure of slope model.Then,get the internal failure shape using Sand layer model,find the critical slip surface location,analyze the process of slope surface crack from production,extension to destruction,and measure pressure in the body of slope soil.Specific to the laboratory model test of three-dimensional slope failure that partial crest loaded,design sand layer model to seek slip surface of slope failure.Based on the slip surface,fitting analyzing by software,and then study the characteristics of the slip surface and sliding rules.Formulate respectively stabilizing pile reinforcement scheme,and conducted reinforcing model test for three-dimensional slope model with different slope shapes(convex and concave slope)to prove the failure modes within the slope,slip surfaces location and slope failure process,measure the strain of pile,pile-top displacement,pressure in the body of slope soil and a series of data.The results of reinforcement model test with stabilizing pile show that:(Ⅰ)The damage process of convex,concave slope all started with the cracks at the peak Angle of loading plate,then spread to the back of the piles,finally damaged to the slope toe,and pushed the stabilizing piles forward continuously.(Ⅱ)Loading force on the convex,concave slope raised fast before reaching the ultimate,then back obviously,and raised again after re-establishing stable equilibrium.(Ⅲ)The slopes present the obvious characteristics of three-dimensional after the destruction of the convex,concave slope,and the fitting sliding surface was smooth curved surface.Convex slope slip surface appeared Arc-shaped on the whole,but with obvious gradient in front of the pile and back of the pile.Concave slope slip surface appeared Apple-shaped.The depth of the Convex slope slip surface was greater than the concave slope.(Ⅳ)The pressure of internal soil in the convex,concave slope changed consistently with load force in the whole loading process.The embedded depth was more shallow,the stress response was more obvious.The embedded depth was more deeper,the stress response was less particularly consistent.(Ⅴ)The anti-slide pile strain in the convex,concave slope showed different changes.The study that compared the four groups earlier tests of described(convex slope,concave slope,reinforcement of convex slope,reinforcement of concave slope)horizontally and vertically shows that:(Ⅰ)Different slope shapes is a very important factor which effect the stability of three-dimensional slope and the characteristics of slip surface of slope after destruction,and concave slope is better stable than convex slope.(Ⅱ)Loading method decides the formation of the slip surface of slope and failure mode of slope.(Ⅲ)The reinforcement using the stabilizing pile for three-dimensional slope is feasible,especially for convex slope.there is a big difference in stress on the pile body.(Ⅳ)When stabilizing piles were applied to different shapes of the slope reinforcement,the stress mainly concentrate on the upper of pile body in convex reinforced slope,but on the lower of pile body in concave reinforced slope.