干拌水泥碎石桩单桩承载力特征值研究  

Study on Characteristics Value of Bearing Capacity of Single Dry Mixed Cement Gravel Pile

作　　者：任涛 REN Tao(China Railway 17th Bureau Group 2nd Engineering Co.Ltd.,Xi’an Shaanxi 710024,China)

机构地区：[1]中铁十七局集团第二工程有限公司,陕西西安710024

出　　处：《铁道建筑技术》2023年第8期93-97,共5页Railway Construction Technology

基　　金：陕西省自然科学基础研究计划项目(2022JM-209)。

摘　　要：基于有限元软件建立干拌水泥碎石桩与软弱路基相互作用数值模型,研究干拌水泥碎石桩单桩承载力与桩身应力分布特征,并分析桩径、桩间距、成桩挤密作用、桩土间接触状态等因素对单桩承载力影响规律。结果表明:干拌水泥碎石桩桩身轴向压力沿深度方向递减;桩身侧摩阻力沿深度方向先减小后增大再减小,最大值出现在距桩端约1.3 m部位;成桩挤密作用对干拌水泥碎石桩单桩承载力影响不大;单桩承载力与地基土模量、路堤土模量和桩土间摩擦系数呈线性关系,且桩土间摩擦系数对单桩承载力影响效果显著。The Cement Gravel Mixing Trenchless(CGMT)pile and weak subgrade interaction numerical model was developed by the finite element software,and employed to study the bearing capacity of single pile and the characteristics of pile stress of CGMT pile.The influences of diameter of pile,pile spacing,lateral compressed effect during the construction,and the interface bonding between pile and soil on the bearing capacity of single pile were analyzed.The results show that the axial pressure of CGMT pile is declining along the deep,and the side friction resistance of CGMT pile is reducing,then increasing,and then declining again along the deep.The maximum side friction resistance of CGMT pile is occurred at the position that is about 1.3 m away from the pile tip.The lateral compressed effect during the construction has few influence on the bearing capacity of single pile.There are linear relationship between the bearing capacity of single pile and the modulus of subgrade,the modulus of embankment,the friction coefficient between pile and soil.In addition,the friction coefficient between pile and soil has significant effect on the bearing capacity of single pile.

关 键 词：公路工程 干拌水泥碎石桩 有限元法 单桩承载力 

分 类 号：TU473.1[建筑科学—结构工程] U416.1[建筑科学—土工工程]