螺杆灌注桩抗拔承载机理的试验研究  

Experimental study on vertical tensile bearing mechanism of screw cast-in-place piles

作　　者：王曙光[1,2] 王浩宇 唐建中 赵志鹏[1] 彭桂皎[3] 王新华 WANG Shuguang;WANG Haoyu;TANG Jianzhong;ZHAO Zhipeng;PENG Guijiao;WANG Xinhua(Institute of Foundation Engineering,China Academy of Building Research,Beijing 100013,China;Disaster Prevention ResearchCenter,Ministry of Housing and Urban-Rural Development,Beijing 100013,China;Hainan Zhuodian High Technique DevelopmentLimited Company,Haikou 570203,China;Chongqing Zhuodian Construction Engineering Co.,Ltd.,Chongqing 401120,China)

机构地区：[1]中国建筑科学研究院地基基础研究所,北京100013 [2]住房和城乡建设部防灾研究中心,北京100013 [3]海南卓典高科技开发有限公司,海南海口570208 [4]重庆卓典建设工程有限公司,重庆401120

出　　处：《岩土工程学报》2023年第10期2156-2164,共9页Chinese Journal of Geotechnical Engineering

摘　　要：通过室内模型试验和现场试验对螺杆灌注桩抗拔承载机理进行了研究,研究表明螺杆灌注桩作为抗拔桩优势较为明显。通过室内模型试验,采用图像处理技术直观地得到上拔荷载作用下螺杆桩和直杆桩的桩周土体位移场和上拔破坏模式,进而对其抗拔承载机理进行探讨,并采用现场试验进行验证。模型试验和现场试验表明,螺杆桩的单桩抗拔承载力高于同直径的等截面桩,螺纹段的抗拔侧阻力与等截面桩的侧阻力相比明显提高。对于螺纹段,极限抗拔侧阻力表现为周边土体的抗剪强度,破坏面为连续的拱形;对于直杆段,极限抗拔侧阻力表现为桩体与桩周土体的摩擦阻力,破坏面为桩周圆柱面。根据试验结果从工程实用的角度,引入抗拔折减系数给出螺杆灌注桩单桩抗拔极限承载力的表达式,并给出相关参数的取值建议。The vertical tensile bearing capacity of the screw cast-in-place pile is studied through the indoor model tests and field tests,and it is shown that the screw cast-in-place pile is superior to be used as the uplift piles.Through the indoor model tests,the failure modes of the screw pile and the straight rod pile by uplift loads are obtained intuitively by using the image processing technology,then the tensile bearing mechanisms are discussed,and the field tests are used for verification.The model and field tests show that the tensile bearing capacity of the single screw pile is higher than that of the straight rod pile with the same diameter,and the tensile lateral resistance of the screw pile is obviously higher than that of the straight rod pile with the same diameter.For the screw section,the tensile ultimate lateral resistance is the shear strength of the surrounding soil,and the fracture surface is a continuous arch.For the straight rod section,the tensile ultimate lateral resistance is the friction resistance between the pile body and the soil around the pile,and the failure surface is the cylinder around the pile.According to the test results and from an engineering practical point of view,the expression for the tensile ultimate bearing capacity of a single screw cast-in-place pile is given by introducing the drawdown coefficient,and the values of the relevant parameters are suggested.

关 键 词：螺杆灌注桩 破坏模式 抗拔承载机理 模型试验 现场试验 

分 类 号：TU473[建筑科学—结构工程]