Evolution Characteristics and Mechanism Analysis of Soil Arch of Anti-slide Pile

Research purposes: Soil arching effect of anti-slide piles is a phenomenon of stress transfer and redistribution of soil caused by itself shear strength, which is of great significance to the safe and economical design of anti-slide piles. At present, there is a lack of research and mechanism analysis on the evolution characteristics of soil arch of anti-slide pile, which makes it difficult for theoretical results of soil arch of anti-slide pile to guide the calculation of pile spacing. In this paper, the development stage of soil arch of anti-slide pile is studied by method of model test and numerical simulation, and the evolution characteristics and mechanism of soil arch of anti-slide pile are analyzed. Research conclusions:(1) The soil arch of anti-slide pile from formation to failure can be divided into three stages, namely formation stage, development stage and failure stage. (2) Model test results show that the soil behind the pile is compressed and deformed under the action of thrust, and then the soil is curved and cracked, and the end-bearing soil arch is formed between the piles; with the increase of load, the thickness of the arch pressure zone increases; when the load increases to a certain extent, the inside of the pile produces longitudinal crack, and longitudinal crack gradually develop backward, leading to soil arch failure. (3) In the initial stage, the stress in the soil arch area is mainly horizontal stress, with the increase of load, the normal stress increases gradually, the direction of principal stress deflects, the soil between piles generates a penetrating shear strain increment zone, and the inside of the arch pressure zone is located at about 2 times the pile width. (4) The research results can provide theoretical guidance for the design and safety evaluation of anti-slide piles engineering. © 2019, Editorial Department of Journal of Railway Engineering Society. All right reserved.