Study On Soil Arching Effect Of Anti-slide Piles And Sliding Instability Of Soil Between Piles

More and more projects construction are on going because of human activities demand, as a result, there are bound to be rock and soil mass excavation or filling. Mechanical equilibrium state is changed due to the transformation of rock and soil mass conducted by human beings. Thus, geo-hazards would be induced, such as, landslides and collapse. With advantages of sufficient lateral resistance, convenient construction and relatively little disturbance to surrounding geological bodies, anti-slide pile is widely applied to geotechnical engineering field, such as, slope treatment and foundation pit bracing. With respect to anti-slide pile supporting slope, present research has being focused on single pile internal-force calculation and soil arch effect after piles. However, a widespread consensus about soil arch effect has not been formed by professions, in addition, there are less research about soil mass instability between piles while soil mass slump and flow around between piles may be incurred without supported.This paper takes anti-slide pile supporting slope as a research objection, analyzing existing research results, combining fundamental theory and numerical simulation to establish own research method. The numerical simulation is a key approach to study spatial distribution characteristics of soil arch effect and sliding surface between piles and their relationship. In order to meet actual projects application, instability-slump between piles, soil arch effect and their interactive relationship is analyzed, and key influence factors is studied. The main research contents and results are as follows:① Fundamental theories of anti-slide pile soil arch effect and soil failure mechanism between piles are analyzed. Three basic research methods of analyzing soil arching effect and sliding surface determine method are determined, which provides a basis for future exploration in this dissertation.② FLAC3 D software is employed to built analysis model, soil arching effect generation and formation, arch height, arch thickness and arch skewbacks are studied. By means of curve fitting technique, spatial distribution of soil arch is obtained. The distribution characteristics of tension-shearing belt and the patterns of sliding surface are analyzed on condition that soil mass collapse between piles. In addition, their spatial distribution relationship and relevant laws are obtained. It’s show that slump in the soil arch in front, with some distance from the front arch, the closer to the symmetry plane between piles,the greater distance. The distance between the front arch and the sliding surface gradually increases with the increase of the depth. And soil pressure calculative range of slab could be figured out based upon that.③ Firstly, soil arch effect variation law is studied during soil mass graded excavation before piles when slope supported by anti-slide piles, which could be provide a basis for excavation and reinforcement of slope appropriately. Then, soil stability between piles affected by excavation is analyzed. Finally, their variation laws are summarized, the influence of soil mass collapse on soil arch effect is discussed. The soil mass collapse renders soil arch retrusion, and the increase of arch height gradually declines as the increase of excavation depth until the tendency of variation remains unchanged. With the increase of the stability of the excavation depth gradually decreased, and the decrease trend slowed down.④ Combining the aforementioned methods to study general laws of soil arch effect and soil mass stability through changing the values of soil strength parameters and distance between piles by adoption of single variable method.