竹筋格栅套筒加筋碎石桩极限承载力计算  

Calculation of Ultimate Bearing Capacity of Gravel Pile Reinforced with Bamboo Grid Sleeve

作　　者：郭跃飞 章本本 罗正东[2] 谢测坤 GUO Yue-fei;ZHANG Ben-ben;LUO Zheng-dong;XIE Ce-kun(Yueyang City Roads and Bridge Construction Corporation,Yueyang 414000,China;College of Civil Engineering,Xiangtan University,Xiangtan 411105,China)

机构地区：[1]岳阳市公路桥梁基建总公司,岳阳市414000 [2]湘潭大学土木工程学院,湘潭市411105

出　　处：《公路》2023年第10期111-117,共7页Highway

基　　金：国家自然科学基金资助项目,项目编号51909086;2021年湖南省研究生科研创新项目(企业联合项目),项目编号21B0123。

摘　　要：基于竹筋格栅套筒加筋碎石桩在竖向荷载作用下的受力变形特征,分析了其承载机理和破坏模式。根据极限平衡理论对两种常见破坏模式下的竹筋格栅套筒加筋碎石桩的单桩极限承载力计算公式进行了理论推导,并得出竹筋格栅抗拉强度和套筒长度是桩体破坏模式的判定依据。结合工程实践案例,探究了竹筋格栅抗拉强度、套筒长度以及桩径对单桩极限承载力的影响规律。结果表明:竹筋格栅套筒通过提供额外的径向约束力有效限制了碎石桩的鼓胀变形,从而大幅提高了碎石桩承载力。同时,竹筋格栅抗拉强度、套筒长度以及桩径3者之间存在最优组合,在实际工程应用中应综合考虑3者之间的影响关系,选取最优组合,从而最大程度上提高碎石桩承载力。Based on the stress and deformation characteristics of the bamboo grid sleeve reinforced gravel pile under vertical load,the bearing mechanism and failure mode are analyzed.According to the limit equilibrium theory,the calculation formula of the ultimate bearing capacity of the single pile of the bamboo grid sleeve reinforced gravel pile under two common failure modes is theoretically deduced,and the tensile strength of bamboo grid and sleeve length are the judging basis of pile failure modes.Combined with an application practice,the influence of the tensile strength of the bamboo grid,the length of the sleeve and the diameter of the pile on the ultimate bearing capacity of the single pile is explored.The results show that the bamboo grid sleeve can effectively limit the bulging deformation of the gravel pile by providing additional radial restraint force,thereby greatly improving the bearing capacity of the gravel pile.At the same time,there is an optimal combination among the tensile strength of bamboo grid,sleeve length and pile diameter.In practical engineering applications,the influence relationship between the three should be considered comprehensively,and the optimal combination should be selected to maximize the improvement of the gravel pile bearing capacity.

关 键 词：加筋碎石桩 竹筋格栅套筒 承载变形机理 极限承载力 破坏模式 

分 类 号：U416.1[交通运输工程—道路与铁道工程] TU473.1[建筑科学—结构工程]