嵌岩桩竖向承载机理的数值分析

Numerical Analysis of Vertical Bearing Mechanism of Rock-socketed Pile

嵌岩桩的极限承载力高，在现场试验中很难将其加载至破坏和监测破坏时分析嵌岩段摩阻力的分布特征．在有限单元法的基础上，采用ANSYS软件，对两个嵌岩桩模型进行了竖向承载机理模拟．分析了桩端阻力在桩顶荷栽中的比例、不同土层侧摩阻力的分布等状况．数值模拟结果表明：嵌岩桩的桩顶荷栽由桩侧摩阻力与桩端阻力共同承担，桩侧阻力占60％～70％，桩端阻力和嵌岩层阻力占30％～40％；土层侧摩阻力达到极限时，桩端阻力和嵌岩层的侧摩阻力还可以进一步的发挥．

In field rock-socketed piles can hardly be loaded to failure tests and monitored the distributed characteristic of rock-socketed layer side friction due to their high ultimate bearing capacity. To simulate the vertical bearing mechanism, two rock-socketed pile models were tested by the ANSYS software based on the finite element method. The proportion of pile-head load, the distribution of side friction in different soil and other related conditions of pile tip resistance were analyzed. The numerical simulation results indicate that top load of rock-socketed pile undertakes together by pile side resistance and pile tip resistance. Pile side resistance accounts for 60-70% of the load, pile tip resistance and rock-socketed layer resistance 30%-40%. When the soil layer side friction reaches a climax, pile tip resistance and rock -socketed layer resistance still work further.