Geomechanics and Engineering

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Optimal design of stone columns reinforced soft clay foundation considering design robustness

  • Yu, Yang (Ocean College, Zhejiang University) ;
  • Wang, Zhu (Ocean College, Zhejiang University) ;
  • Sun, HongYue (Ocean College, Zhejiang University)
  • Received : 2019.12.02
  • Accepted : 2020.07.10
  • Published : 2020.08.25
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Abstract

Stone columns are widely used to treat soft clay ground. Optimizing the design of stone columns based on cost-effectiveness is always an attractive subject in the practice of ground treatment. In this paper, the design of stone columns is optimized using the concept of robust geotechnical design. Standard deviation of failure probability, which is a system response of concern of the stone column-reinforced foundation, is used as a measure of the design robustness due to the uncertainty in the coefficient of variation (COV) of the noise factors in practice. The failure probability of a stone column-reinforced foundation can be readily determined using Monte Carlo simulation (MCS) based on the settlements of the stone column-reinforced foundation, which are evaluated by a deterministic method. A framework based on the concept of robust geotechnical design is proposed for determining the most preferred design of stone columns considering multiple objectives including safety, cost and design robustness. This framework is illustrated with an example, a stone column-reinforced foundation under embankment loading. Based on the outcome of this study, the most preferred design of stone columns is obtained.

Keywords

Acknowledgement

The authors wish to acknowledge the financial support of the National Natural Science Foundation of China (41807224) and the Natural Science Foundation of Zhejiang Province (LQ17D020001). The first author wishes to thank Dr. C. Hsein Juang for his kindly help on the research of robust geotechnical design.

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