嵌岩桩极限端阻力发挥性状研究

Characterization of End-Bearing Capacity for Piles Socketed into Rocks

摘要: 端阻力承载性状是岩土工程中嵌岩桩应用的重要研究课题之一。本文分别根据嵌岩桩下压承载力计算模型以及嵌岩桩端阻力分担桩顶荷载的理论计算公式，分析了下压荷载作用下嵌岩桩端阻力发挥特征，并与已有试验实测结果进行对比。结果表明，下压荷载作用下嵌岩桩承载特性主要呈现为端承摩擦桩，端阻分担桩顶荷载随嵌岩深径比增大而减小，随桩体混凝土与桩周岩体的模量比增大而增大，并与嵌岩段桩端与桩身周围岩体的弹性模量比相关，研究成果可为嵌岩桩极限端阻力设计提供借鉴。

Abstract: It is an important issue to investigate the characteristics of end-bearing capacity for the application of rock-socketed piles. In this study, based on the theoretical calculation formula of end-bearing load sharing ratio of rock-socketed pile, the characteristics of end-bearing capacity of rock-socketed pile were analyzed. The results indicated that the end-bearing capacity characteristics of rock-socketed piles were mainly end-bearing friction piles and the load ratio of ultimate end-bearing capacity decreased with the increase of rock-socketed depth-diameter ratio but in-creased with the elastic modulus ratio of pile concrete to surrounding rock mass, which is similar to the field test results. At the same time, it is related to the elastic modulus ratio of rock-socketed pile tip and surrounding rock mass. The relevant variation law in this study can be used for the design of ultimate end-bearing capacity of rock-socketed piles in practice.