一种高切坡超前支护桩的作用机制

Study on the Mechanism of a Kind of Pre-reinforced Pile

高切坡超前支护桩能有效地抑制边坡的变形,确保开挖边坡的稳定性。但常规钢筋混凝土超前支护桩的刚度大,导致施加在桩体上的土压力较大,为解决这一问题,提出在超前支护桩体靠山侧设置一层EPS垫层材料以降低超前支护桩与变形坡体之间的作用力。采用数值分析方法,研究了EPS垫层材料类型、厚度、刚度对超前支护桩土压力、桩身变形以及桩身内力的影响,揭示了EPS垫层材料对超前支护桩作用机制的影响。研究结果表明:EPS垫层的厚度和密度对超前支护桩桩土共同作用有显著影响。超前支护桩后布置的EPS垫层厚度越大,超前支护桩上的土压力越小,桩身位移越小,桩身内力越小;超前支护桩后布置的EPS垫层密度越小,超前支护桩上的土压力越小,桩身位移越小,桩身内力越小。

Pre-reinforced pile in high cutting slope can reduce the displacement of the slope and ensure the stabilization of the slope.Because of the largely structural stiffness of concrete pre-reinforced pile,the earth pressure acting on pile increases.In order to settle this problem,a layer of EPS backs on to the pre-reinforced pile was set to decrease the interaction force of pre-reinforced piles.Finite element analysis software of ANSYS was used to analyze the value and distribution of displacement,shearing force and bending moment acted on the pre-embedded pile with different thickness and types of EPS backs on to the pre-reinforced pile.The results showed that the thickness and types of EPS have large influence on pre-reinforced piles.With the increase of the thickness of EPS,the earth pressure acting on pile decreases,the displacement of pre-reinforced pile decreases,and the inner force of pre-reinforced pile decreases.With the decrease of the density of EPS,the earth pressure acting on pile decreases,the displacement of pre-reinforced pile decreases,and the inner force of pre-reinforced pile decreases.