CLC number: TU4
On-line Access: 2018-04-04
Received: 2017-09-26
Revision Accepted: 2017-12-13
Crosschecked: 2018-03-07
Cited: 0
Clicked: 4305
Hai-zuo Zhou, Gang Zheng, Xiao-xuan Yu, Tian-qi Zhang, Jing-jin Liu. Bearing capacity and failure mechanism of ground improved by deep mixed columns[J]. Journal of Zhejiang University Science A, 2018, 19(4): 266-276.
@article{title="Bearing capacity and failure mechanism of ground improved by deep mixed columns",
author="Hai-zuo Zhou, Gang Zheng, Xiao-xuan Yu, Tian-qi Zhang, Jing-jin Liu",
journal="Journal of Zhejiang University Science A",
volume="19",
number="4",
pages="266-276",
year="2018",
publisher="Zhejiang University Press & Springer",
doi="10.1631/jzus.A1700517"
}
%0 Journal Article
%T Bearing capacity and failure mechanism of ground improved by deep mixed columns
%A Hai-zuo Zhou
%A Gang Zheng
%A Xiao-xuan Yu
%A Tian-qi Zhang
%A Jing-jin Liu
%J Journal of Zhejiang University SCIENCE A
%V 19
%N 4
%P 266-276
%@ 1673-565X
%D 2018
%I Zhejiang University Press & Springer
%DOI 10.1631/jzus.A1700517
TY - JOUR
T1 - Bearing capacity and failure mechanism of ground improved by deep mixed columns
A1 - Hai-zuo Zhou
A1 - Gang Zheng
A1 - Xiao-xuan Yu
A1 - Tian-qi Zhang
A1 - Jing-jin Liu
J0 - Journal of Zhejiang University Science A
VL - 19
IS - 4
SP - 266
EP - 276
%@ 1673-565X
Y1 - 2018
PB - Zhejiang University Press & Springer
ER -
DOI - 10.1631/jzus.A1700517
Abstract: Extensive research has investigated the bearing capacity of footings placed on leveled ground improved by deep mixed (DM) columns. However, few studies have focused on the effects of the embedment on the bearing capacity of footings on ground reinforced with DM columns. In geotechnical engineering practice underestimation of the limit load has occurred in China because of the increased use of conventional design methods for reinforced ground with embedment. In this investigation, a numerical model using a rigorous limit analysis tool, known as discontinuity layout optimization (DLO), is established. An equivalent area model is employed with an appropriate stress concentration ratio. Subsequently, a set of design charts of bearing capacity coefficients is produced with a special focus on the bearing capacity coefficient Nq and the failure mechanism. The results show that three failure patterns exist in the composite ground reinforced by DM columns. For cases without embedment, the bearing capacity coefficient Nc increases with the area replacement ratio to a certain value due to the occurrence of general shear failure mechanism. The bearing capacity coefficient Nγ decreases with the area replacement ratio, as the equivalent frictional strength of the reinforced region is reduced. When the embedment is considered, the failure mechanism of composite foundation has a significant influence on the coefficient Nq. Specifically, increase of column length leads to a larger value of Nq when block failure is observed. When a general shear failure pattern occurs, the effect of additional column lengths on the coefficient Nq can be neglected.
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