Study On The Interaction Mechanism Of Micro-anti-sliding Pile Group And Landslide Based On Soil Arching Effect

In the southwest of the mountain is very high,the road is very danger,geological disasters occur frequently,in all kinds of geological disasters,the most is the landslide,the landslide will not only cause significant economic losses,but also will cause heavy casualties,landslide disaster seriously threatening the local people's life and property safety,there are a lot of landslide prevention methods in engineering,and anti-slide pile is one of the most effective.But the structure of traditional anti-slide pile is very large,it will take a long construction period,construction process is very complex,and requires large mechanical equipment and excellent construction conditions,the traditional anti-slide pile is difficult to use in the emergency rescue,based on the "fast,safe,economy" concept of prevention,Miniature anti-slip pile group is becoming more and more widely in the application of the slope reinforcement.Considering the soil arch effect between pile soil interaction is one of the most important aspects of the anti-slide pile research,research on traditional anti-slide pile soil arch effect has been more in-depth,for micro anti-sliding pile group,the usual practice is to traditional anti-slide pile in the theory of analogy to tiny anti-sliding pile group,but because of the particularity of the micro structure of pile,it is not reasonable,in order to further study the micro pile group-landslide interaction relations,especially in FLAC3D6.0 Finite Difference Software numerical simulation experiment was carried out,the main work and achievements are as follows:(1)Based on the calculation theory of soil arching effect of traditional anti-slide piles,the differences between traditional anti-slide piles and micro-pile group structures are compared and analyzed,the interaction process between micro-pile group and landslide is summarized,and the formulas of maximum and minimum pile spacing of micro-pile group based on soil arching effect are deduced.(2)A row of tiny anti-slide pile and soil interaction will change along the direction of the pile length,the interaction from the pile top to near the sliding surface will be more and more strong,in three rows of the plum flower form in the layout of vertical micro pile group,the back of pile and soil interaction trend is the same as the single row pile,but in the bottom of the piles and piles in the front row,this effect is a trend of weakening.(3)Quincunx decorate a tiny group of pile of pile soil interaction than parallel arrangement of miniature pile group interaction of more intense,the distance between row and row and column and the distance between the columns of a tiny group of pile has obvious influence of the soil arch effect,and the numerical test results show that when the distance between row and row and column and the distance between the columns is five times the pile diameter,pile soil interaction best,5 times the pile diameter is the most reasonable pile spacing and row spacing.(4)When the front row and back row micro piles have a certain Angle,under the action of horizontal load,the back row pile will produce a large tensile stress,change the pile inclination,and the interaction between pile and soil will change obviously.The research shows that the micro piles have the best bearing performance when the front and back pile inclination is 15°?20°.(5)Through the comparison of numerical simulation test and engineering practice,it is found that the reasonable pile spacing formula of micro-pile based on soil arching effect between piles derived in this paper is consistent with the engineering practice,and the application of micro-pile anti-sliding group can significantly improve the slope stability coefficient,which is a good landslide rescue measure.