潜孔冲击水泥土复合预制桩承载特性研究  

Research on Vertical Bearing Characteristics of Down the Hole Jet Grouting Composite Prefabrication Pile

作　　者：孙雅珍[1] 李卿辰 耿琳 魏少伟 姚建平 SUN Yazhen;LI Qingchen;GENG Lin;WEI Shaowei;YAO Jianping(School of Transportation and Geomatics Engineering,Shenyang Jianzhu University,Shenyang,China,110168;Beijing Tieke Special Engineering Technology Corporation Limited,Beijing,China,100081;Railway Construction Research Institute,China Academy of Railway Sciences Corporation Limited,Beijing,China,100081)

机构地区：[1]沈阳建筑大学交通与测绘工程学院,辽宁沈阳110168 [2]北京铁科特种工程技术有限公司,北京100081 [3]中国铁道科学研究院集团有限公司铁道建筑研究所,北京100081

出　　处：《沈阳建筑大学学报（自然科学版）》2022年第6期1088-1095,共8页Journal of Shenyang Jianzhu University：Natural Science

基　　金：国家杰出青年科学基金项目(51825803);中国国家铁路集团有限公司科技研究开发计划(N2019G60)。

摘　　要：目的 研究荷载下潜孔冲击水泥土复合预制桩(DJC桩)的承载特性,为该新型桩的工程设计提供参考。方法 结合浙江石化炼化一体化项目,通过室内模型试验、数值模拟和现场试验3种方法研究该桩的荷载传递机理,并基于PLAXIS软件分析芯长比、含芯率和界面参数对DJC桩承载特性的影响。结果 竖向荷载下管桩承担主要荷载,管桩轴力约是水泥土桩轴力的1.8倍,管桩轴力与水泥土轴力分布规律相似;内侧摩阻力和外侧摩阻力均随深度呈现先递增后递减的趋势,内侧摩阻力约是外侧摩阻力的1.75倍;桩基整体质量较好,芯长比、含芯率和界面参数对桩基承载特性均有影响,但含芯率的影响更大,合理的含芯率在0.5~0.6。结论 DJC桩能有效地解决复杂地层下的地基处理问题,芯长比和含芯率取值可为实际工程提供参考。The bearing characteristics of DJC piles under load are studied to provide reference for the engineering design of this new type of piles.To explore the bearing characteristics and the load transfer mechanism of DJC piles, a series of indoor model tests, numerical simulations and field tests were performed.Combined with the Zhejiang petrochemical refining and chemical integration project, the effects of core length ratio, core content, and interface parameters on the bearing characteristics of DJC piles were analyzed based on PLAXIS software.A comparison of the axial forces of pipe pile and cement-soil pile confirms that the main load under the vertical load is borne by the pipe pile, which is about 1.8 times that of the cement-soil pile, and the distribution law of the axial force of the pipe pile is similar to that of the cement-soil pile.Both the inner and the outer friction resistance increase first and then decrease with the increasing depth, and the inner friction resistance is about 1.75 times outer.Furthermore, the overall quality of the pile foundation is good, and the bearing characteristics of the pile foundation are affected by the core length ratio, the core content ratio, and the interface parameters.Among the parameters, the core content ratio, with the reasonable range of 0.5~0.6,has a wider range of influence.DJC pile can effectively solve the problem of foundation treatment under complex formation, and the value of core length ratio and core content can provide reference for actual engineering.

关 键 词：潜孔冲击水泥土复合预制桩(DJC桩) 承载特性 荷载传递机理 界面接触本构 

分 类 号：TU473[建筑科学—结构工程]