(1 华东建筑设计研究院有限公司地下空间与工程设计研究院, 上海 200002; 2 广州市建筑集团有限公司, 广州 510030; 3 广州大学土木工程学院, 广州 510006)

摘要: 静钻根植桩因其兼顾高承载性能和绿色环保的优势而逐步在上海地区得到应用. 虽然上海市《地基基础设计标准》(DGJ 08-11—2018)已将植入桩工法纳入到预制桩的推荐施工工法中,但并未提出相关的承载力计算细则,给静钻根植桩设计与应用带来了难度与不确定性. 借鉴日本植入桩的承载力计算思路,等效为预制桩直径计算侧阻力,结合上海地区估算桩基承载力的经验,以单桥静力触探比贯入阻力为基本参数,引入侧阻力调整系数和扩大头阻力系数分别计算桩侧阻力和端阻力,提出了一种实用的静钻根植桩竖向承载力计算方法. 工程实例计算表明,该承载力计算方法具有一定的可靠性,可为上海地区静钻根植桩设计提供参考.

关键词: 静钻根植桩; 承载力; 计算方法; 静力触探比贯入阻力; 静载试验

中图分类号:TU473. 1 文献标志码:A 文章编号:1002-848X(2023)08-0137-06

DOI:10. 19701 / j. jzjg. 20210030

Calculation method of bearing capacity of pre-bored precast pile with enlarged base by index of CPT

WU Jiangbin1, LING Zao2,3, WANG Weidong1, HU Yun1

(1 Underground Space & Engineering Design & Research Institute, East China Architecture Design & Research InstituteCo. , Ltd. , Shanghai 200002, China; 2 Guangzhou Municipal Construction Group Co. , Ltd. , Guangzhou 510030,China; 3 School of Civil Engineering, Guangzhou University, Guangzhou 510006, China)

Abstract: The pre-bored precast pile with enlarged base (PPEB pile) has been gradually applied in Shanghai area becauseof its advantages of high bearing capacity and green environmental protection. Although the embedded pile method has beenincorporated into the recommended construction method of pre-bored precast pile in the Shanghai Foundation design code(DGJ 08-11—2018), but the relevant detailed rules for calculating the bearing capacity have not been put forward, whichbrings difficulty and uncertainty to the design and application of PPEB pile. The idea of calculating the bearing capacity ofpre-bored precast piles in Japan was used for reference, the equivalent diameter of pre-bored precast piles was used tocalculate the shaft resistance. Combined with the experience of estimating the bearing capacity of pile foundation inShanghai area, the specific penetration resistance of single bridge CPT was taken as the basic parameter. The shaftresistance adjustment coefficient and the toe resistance coefficient were introduced to calculate the shaft resistance and toeresistance respectively, and a practical method for calculating the vertical bearing capacity of PPEB pile was put forward.The calculation of engineering example shows that the calculation method of bearing capacity is reliable and can providereference for the design of PPEB pile in Shanghai area.

Keywords:pre-bored precast pile with enlarged base; bearing capacity; calculation method; specific penetration resistanceof CPT; static load test

∗上海市优秀学术/ 技术带头人计划(18XD1 422600),上海市青年科技启明星计划 (18QB1 400300).

第一作者:吴江斌,博士,教授级高级工程师,主要从事高层建筑地基基础、地基处理、地下工程的设计与研究,Email:jiangbin_wu@ ecadi. com.

[引用本文] 吴江斌 ,凌造,王卫东,等. 基于静力触探试验指标的静钻根植桩承载力计算方法[ J]. 建筑结构,2023,53(8):137-142. WU Jiangbin,LING Zao,WANG Weidong,et al. Calculation method of bearing capacity of prebored precast pile with enlarged base by index of CPT [J]. Building Structure,2023,53(8):137-142.