覆盖岩溶临空面对水平承载桩嵌固端承载力的影响试验研究  

EXPERIMENTAL STUDY ON INFLUENCE OF COVERED KARSTIC FREE SURFACE ON FIXED END BEARING CAPACITY OF LATERALLY LOADED PILE

作　　者：李天雨 范秋雁 韩伟 梁家珲 LI Tian-yu;FAN Qiu-yan;HAN Wei;LIANG Jia-hui(Research Center of Geotechnical and Structural Engineering,Shandong University,Ji'nan,Shandong 250061,China;School of Resources,Environment and Materials,Guangxi University,Nanning,Guangxi,530004,China;Guangxi Communications Investment Technology Co.,Ltd.Nanning,Guangxi,530022,China)

机构地区：[1]山东大学岩土与结构工程研究中心,山东济南250061 [2]广西大学资源环境与材料学院,广西南宁530004 [3]广西交投科技有限公司,广西南宁530022

出　　处：《工程力学》2020年第10期192-199,共8页Engineering Mechanics

基　　金：国家自然科学基金项目(41162012);广西地区基金项目(2010GXNSFA013005)。

摘　　要：岩溶地区基岩岩面起伏很大,当水平承载桩嵌固在覆盖岩溶临空面附近时,覆盖岩溶临空面可能会失稳,导致嵌固端失去承载能力。该文设计了含覆盖岩溶临空面和一个软弱结构面组合地质条件下的嵌固端室内模型,考虑了临空面在桩前和临空面在桩后两种工况。进行水平加载试验后,结果表明:临空面和结构面的存在降低了嵌固端的承载力,且桩前临空面对桩嵌固端承载力的影响更显著。在此基础上,基于极限平衡法,提出了含覆盖岩溶临空面和结构面的嵌固端岩体承载力验算方法,并通过比较计算结果和试验结果,对计算假设条件和计算方法进行了验证。Bedrock surface in karst region is undulating.When laterally loaded piles are fixed nearby covered karstic free surface,the destabilization of the pile may occur and result in the loss of fixed-end bearing capacity.An interior fixed-end model with combined geological conditions of a covered karstic free surface and a weak structural plane is designed,and two working conditions are considered:the free surface is absence of the pile and the free surface is inserted the pile.A lateral loading test was conducted and proved that the existence of the free surface and the structural plane reduces the fixed-end bearing capacity,and that the impact of the free surface before pile is more significant.Based on this result and the limit equilibrium method,a method for calculating the fixed-end bearing capacity of rock mass containing covered karstic free surface and structural plane is proposed.Calculation and test results were compared to validate the assumptions and the method.

关 键 词：覆盖岩溶临空面 水平承载桩 结构面 极限平衡法 嵌固端承载力 

分 类 号：TU458.4[建筑科学—岩土工程]