带扩大桩靴桩基施工挤土效应解析研究  

Analytical study on soil squeezing effect during pile construction with enlarged spudcan

作　　者：吴君涛 耿少寒 梁一然 王奎华[1,2] 应晓阳 WU Juntao;GENG Shaohan;LIANG Yiran;WANG Kuihua;YING Xiaoyang(College of Civil Engineering and Architecture,Zhejiang University,Hangzhou 310058,China;Center for Balance Architecture,Zhejiang University,Hangzhou 310063,China;The Architecture Design and Research Institute of Zhejiang University Limited Company,Hangzhou 310027,China;Zhejiang Dadi Geological Survey and Design Limited Company,Hangzhou 310030,China;Zhongtian Construction Group Limited Company,Hangzhou 310016,China)

机构地区：[1]浙江大学建筑工程学院,浙江杭州310058 [2]浙江大学平衡建筑研究中心,浙江杭州310063 [3]浙江大学建筑设计研究院有限公司,浙江杭州310027 [4]浙江大地勘测设计有限公司,浙江杭州310030 [5]中天建设集团有限公司,浙江杭州310016

出　　处：《浙江大学学报（工学版）》2024年第1期130-139,共10页Journal of Zhejiang University：Engineering Science

基　　金：国家自然科学基金资助项目(52108349,52178358);浙江省自然科学基金重点资助项目(LXZ22E080001)。

摘　　要：提出新型带扩大桩靴预应力管桩基础.不同于均匀截面管桩的施工挤土效应,由于桩靴尺寸大于预制管桩桩身,桩端扩张不宜视作理想球体而更接近于扁球体(旋转椭球体).基于扁球体扩张源对新型带扩大桩靴桩基施工挤土位移场进行解析求解,基于圆孔扩张理论考虑桩周土塑性区域的体积变形,对扁球体扩张应变路径法计算结果进行修正.通过提出的解析解,研究带扩大桩靴桩基施工挤土效应.结果表明,桩周场地可以根据位移场分布规律,大致分为近地表、近桩端以及桩身附近3个区域.扩张源形态越“扁”,桩身附近区域水平“排开”效应略有增强,近地表区域地面“隆起”位移及近桩端区域竖向位移显著减小,这对于挤土桩施工而言是非常有益的.A new pre-stressed pipe pile foundation with enlarged spudcan was proposed.Different from the soil squeezing effect of pipe piles with uniform section,the expansion of the pile toe can not be regarded as an ideal sphere by considering the dimension of the spudcan is larger than that of the prefabricated pipe pile,but is much closer to an oblate spheroid(rotational ellipsoid).The construction squeezing displacement field around the new pile foundation with enlarged spudcan was analytically solved based on an oblate spheroid expansion source,and the volume deformation of the plastic region of soil around the pile was considered based on the cavity expansion theory.The calculation results of the oblate spheroid expansion strain path method were modified.The soil squeezing effect of pile foundation with enlarged spudcan was analyzed by employing the analytical solution.Results show that the surrounding soil can be roughly divided into three areas as near the ground surface,near the pile toe and near the pile shaft according to the distribution of the displacement field.The horizontal“squeezing”effect in the area near the pile shaft is slightly enhanced as the shape of the expansion source is more“flat”,while the“uplift”displacement in the area near the ground surface and the vertical displacement in the area near the pile toe are significantly reduced,which is very beneficial for the construction of the squeezing soil type piles.

关 键 词：扩大桩靴 管桩 应变路径法 圆孔扩张 挤土效应 

分 类 号：TU437[建筑科学—岩土工程]