土工基础

›› 2019, Vol. 33 ›› Issue (4): 504-509.

• 工程实录 • 上一篇    下一篇

成都软质岩灌注桩竖向承载性能现场试验与分析

邹 力1，李昭颖2，肖世国2，宋 倩2   

  1. （1.成都市建工科学研究设计院，成都 610051；2.西南交通大学 地质工程系，成都 610031）
  • 收稿日期:2018-11-16 修回日期:2018-12-05 出版日期:2019-08-20 发布日期:2019-08-16
  • 通讯作者: 肖世国(1973-),男,博士,教授,博导,研究方向为边坡与基础工程。
  • 作者简介:邹 力(1982-),男,博士,高级工程师,研究方向为岩土工程咨询、检测与科研。
  • 基金资助:

    国家自然科学基金项目(51578466)

Field Testing and Analysis of Vertical Resistance of Bored Piles in Soft Rock in Chengdu

ZOU Li1, LI Zhaoying2, XIAO Shiguo2, SONG Qian2   

  1. (1.Chengdu Construction Engineering Science Research and Design Institute, Chengdu 610051;
    2.Department of Geological Engineering, Southwest Jiaotong University, Chengdu 610031)
  • Received:2018-11-16 Revised:2018-12-05 Online:2019-08-20 Published:2019-08-16

摘要： 为获得成都地区软质岩灌注桩的竖向承载性能与特征，基于该地区两根软质岩灌注桩的单桩竖向静载荷试验，采用分布式光纤设备开展桩身应力监测，并结合两根试桩的数值模拟分析，综合确定出桩身轴力、桩侧摩阻力、桩端阻力的大小及分布规律，得到桩身侧摩阻力沿深度呈增大变化特征，且在地层分界处，侧摩阻力曲线发生明显突变；随着桩顶荷载增大，桩端阻力逐渐增强，桩端附近的侧摩阻力也逐渐增大，且这种侧摩阻力强化效应主要集中在桩端以上1 m以内。

关键词: 软质岩, 灌注桩, 桩侧摩阻力, 桩端阻力, 竖向承载力

Abstract: Two static axial compressive loading tests on bored reinforced concrete piles that socketed into soft rock to obtain the vertical resistance characteristics of these bored pies. The shaft load transfer was measured by the instrumented fiber optic lines. Combined with the numerical analysis, the axial stress, shaft and tip resistances could be separated. The axial compressive static load test results on bored piles indicate that the shaft resistance increases with the depth to the pile tip; further, at the location of soil stratigraphy change, the obvious shaft resistance changes could be observed. The shaft resistance also increases with the increase of applied axial load. The increased shaft resistance are one meter above the tip of bored pile.

Key words: soft rock, bored piles, skin friction, tip resistance, axial capacity