Experimental study on bearing capacity of large diameter long auger bored pile in weathered rock foundation

被引：0
|
作者：
Bai X. [1 ,2 ]
Zhang M. [1 ,2 ]
Yan N. [3 ]
Kuang Z. [1 ]
Mu Y. [1 ]
Chen X. [1 ]
机构：
[1] School of Civil Engineering, Qingdao University of Technology, Qingdao
[2] Collaborative Innovation Center of Engineering Construction and Safety in Shandong Blue Economic Zone, Qingdao University of Technology, Qingdao
[3] College of Environmental Science and Engineering, Qingdao University, Qingdao
来源：
Bai, Xiaoyu (baixiaoyu538@163.com) | 2018年 / Central South University of Technology卷 / 49期
基金：
中国国家自然科学基金;
关键词：
Load transfer; Long auger bored pile; Side friction; Size effect coefficient of pile side; Strong weathered granite gneiss;
D O I：
10.11817/j.issn.1672-7207.2018.12.023
中图分类号：
学科分类号：
摘要：
Based on results of the vertical compressive static load test conducted on three large-diameter long auger bored piles socket into weathered rock, the bearing capacity and deformation characteristics were studied. The results show that the load-displacement(Q-s) curves of the three test piles initially change slowly and then decrease steeply. The settlement of the pile top is larger than 80 mm and the vertical ultimate bearing capacity of single pile cannot meet the design requirements. The residual settlement of the pile top reaches 92.0%-95.1%, with the rebound rate being between 4.9% and 8.0%, and the elastic working behavior of the piles is not obvious, showing the characteristics of the end bearing frictional pile. Under the test conditions, the ultimate friction resistance of the test pile reduces compared with the value recommended by JGJ 94-2008 "Technical code for building pile foundation" in the loose silty-fine sand, the slightly dense medium-coarse sand, the hard plastic clay, the whole weathered hard rock and the strong weathered hard rock, while increases greatly in the slightly dense-dense coarse sand and the coarse sand. Therefore, the long auger bored pile should be carefully used in the rock and soil layers. Compared with the recommended value in JGJ 94-2008 "Technical code for building pile foundation", the pile side size effect coefficient of three piles reduces by 17.0%-74.0% in the embedded rock section. In the non-embedded section, sand and gravel soil increase by 20.0%-126.0%, while in clay decrease by 7.0%-43.0%. © 2018, Central South University Press. All right reserved.
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页码：3087 / 3094
页数：7
相关论文
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