（1 金陵科技学院， 南京  211169； 2 江苏鸿基节能新技术股份有限公司， 南京 210019；3 东南大学土木工程学院， 南京 210096）

［摘要］在全截面加筋方案基础上提出了一种局部加强型管桩设计方案，并开展了局部加强型预应力管桩抗弯试验，建立了局部加强型预应力管桩的初始抗弯刚度和刚度折减系数、抗裂弯矩和抗弯承载力计算模型。结果表明：对预应力管桩进行局部加强能够显著提高标准管桩的抗弯性能；建立的局部加强型预应力管桩初始抗弯刚度、抗裂弯矩和抗弯承载力设计公式的计算结果与试验结果符合良好，能够直接用于设计计算；建议局部加强型预应力管桩的刚度折减系数取0-28；鉴于局部加强型预应力管桩抗弯承载力大，可扩大其在深基坑支护工程中的应用范围。

［关键词］局部加强型预应力管桩； 抗弯承载力； 抗裂弯矩； 抗弯刚度； 刚度折减系数

中图分类号：TU473文献标识码：A文章编号：1002-848X(2017)09-0080-05

Investigation on bending experiment and design calculation method for locally reinforced PHC pipe pile

Song Yongsheng1, Tao Wencheng2, Yang Bo2, Wei Longwu2, Guo Tong3, Wei Hai2

(1 Jinling Institute of Technology, Nanjing 211169, China; 2 Jiangsu Hongji Energy-saving New Technology Company, Nanjing 210096，  China; 3 School of Civil Engineering, Southeast University, Nanjing 210096，  China)

Abstract:On the basis of a full-section strengthening project, the design scheme of locally reinforced PHC pipe pile was proposed. Bending experiment was carried out for the locally reinforced PHC pipe pile, and calculation models of the initial bending stiffness and stiffness reduction factor, crack  bending moment and bending  bearing capacity of locally reinforced PHC pipe pile were established. Results show that the local strengthening of the PHC pipe piles can significantly improve the bending behavior of the standard pipe piles. Calculation results design formulas of initial bending stiffness, crack bending moment and bending design capacity of locally reinforced PHC pipe pile are in good agreement with the test results, and the formulas can be used for design calculations. It is suggested that the  stiffness reduction coefficient of the locally reinforced PHC pipe pile is 0-28. In view of the large bending bearing capacity of the locally reinforced PHC pipe pile, its application can be expanded in deep foundation pit support engineering.

Keywords:locally reinforced PHC pipe pile; bending bearing capacity; cracking moment; bending stiffness; stiffness reduction factor

*住房与城乡建设部科技项目计划（2013-S2-1），南京市城市建设投资控股（集团）有限责任公司科研项目，金陵科技学院高层次人才工作启动费资助项目（jit-b-201614）。

作者简介：宋永生，博士，讲师，Email：songys@jit.edu.cn。