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| Model tests on the negative skin friction of a pile in unconsolidated soft clay foundation with various initial water contents |
| GU Chuan1，2，WANG Linwei1，2，WANG Jun1，2，ZHANG Tingting3，CAI Yuanqiang4，LIN Gang5 |
| (1. College of Civil Engineering and Architecture，Wenzhou University，Wenzhou，Zhejiang 325035，China；2. The Key Laboratory of Engineering and Technology for Soft Soil Foundation and Tideland Reclamation of Zhejiang Province，Wenzhou University，Wenzhou，Zhejiang 325035，China；3. School of Civil Engineering and Architecture，Wenzhou Polytechnic，Wenzhou，Zhejiang 325035，China；4. College of Civil Engineering，Zhejiang University of Technology，Hangzhou，Zhejiang 310014，
China；5. Zhejiang Province Geological and Mineral Engineering Investigation Institute Co.，Ltd.，
Hangzhou，Zhejiang 310012，China) |
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Abstract The soft clay foundation formed by tideland reclamation is generally unconsolidated. To study the behavior of negative skin friction of a pile in unconsolidated soft clay foundation，4 single-pile model tests were performed，in which different initial water contents of soft clay and two working conditions including self-weight consolidation and surcharge were considered. The characteristics of relative displacement between pile and soil，axial force of pile，negative skin friction and neutral plane position were investigated based on the test results. In both self-weight consolidation and surcharge conditions，the increase of the initial water content leads to the increase of pile settlement，clay settlement，axial force of pile and negative skin friction，and the decrease of the initial water content induces the rise of neutral plane position. In the condition of surcharge，the increase of vertical load leads to the drop of neutral plane position，while in the condition of self-weight consolidation the consolidation time has little effects on the position of neutral plane. In engineering practice，the initial water content of clay foundation should be pained attention since it would cause the increase of negative skin friction and pile axial force.
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2022, Vol. 41 
