Experimental study on simulated driven pile and immersion static load in undisturbed mudstone

被引:0
|
作者
Bai X. [1 ,2 ]
Zhang Y. [1 ,2 ]
Yin J. [1 ,2 ]
Wang Y. [1 ,2 ]
Sang S. [1 ,2 ]
Yan N. [1 ,2 ]
机构
[1] College of Civil Engineering, Qingdao University of Technology, Shandong, Qingdao
[2] Shandong Provincial Colleges, Universities Blue Economic Zone Engineering Construction and Safety Collaborative Innovation Center, Qingdao University of Technology, Shandong, Qingdao
基金
中国国家自然科学基金;
关键词
damage; driven piles; pile foundations; pin-penetration test; submerged static load test; undisturbed mudstone;
D O I
10.13722/j.cnki.jrme.2022.0705
中图分类号
学科分类号
摘要
In order to study the bearing capacity of dynamic driving pile in mudstone foundation,the influence of driving process and water on the mechanical properties of mudstone is considered. The model tests of pile driving and static load,needle penetration test and electronic magnifying glass test were carried out. Combined with the field test data,the penetration characteristics and bearing capacity of the driven pile are analyzed,and the damage characteristics of mudstone around the pile are clarified. The results shows that:(1) the mudstone has strong heterogeneity,and the soft and hard interbedded phenomenon is significant. The maximum strength is 13.5 times of the minimum value,and the variation trend of mudstone strength and hammering number is synchronous. (2) The strength of the mudstone at the soft interlayer decreases by 64.2% on average after immersion,and the static load test is damaged by large settlement at the soft interlayer,and the steep drop characteristics are the same as the field test. (3) The damage range of pile driving is 2d(d is pile diameter). The strength of mudstone decreases by 66%,40.5%,17% and 7% on average in 0‐0.5d,0.5d‐1.0d,1.0d‐1.5d and 1.5d‐2.0d around the pile. (4) There is compaction relaxation phenomenon at the pile end. The strength of mudstone at the pile end is 11.1% higher than that at 2d around the pile,and 194.5 % higher than that at the same position of the pile. (5) Mudstone heterogeneity is the cause of mudstone pile bearing capacity problem,which is easy to be ignored in geologic investigation. It is considered that mudstone is always uniform,stable,and its strength increases with depth. This phenomenon should be recognized and paid attention to. © 2023 Academia Sinica. All rights reserved.
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页码:1287 / 1300
页数:13
相关论文
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