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| Analysis of load-settlement relationship of new and old piles in natural saturated clays |
| LI Jingpei1，2，ZHANG Lingxiang1，2，LI Lin1，2，LIU Zhenxing3 |
| (1. Key Laboratory of Geotechnical and Underground Engineering of Ministry of Education，Tongji University，Shanghai 200092，China；2. Department of Geotechnical Engineering，Tongji University，Shanghai 200092，China；3. Shanghai Changkai Geotechnical Engineering，Shanghai 200070，China) |
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Abstract Due to the reconsolidation after pile installation，mechanical properties of soil around old piles are extremely different from soil around new piles. Considering pile-jacking influence and initial anisotropy properties of the natural clay and adopting an analytical solution to elastoplastic cavity expansion due to the pile jacking-in，the mechanical characteristics of soil around the new and old piles are subsequently analyzed in detail. On this basis，load transfer models are proposed for new and old piles respectively according to the different mechanical properties in this paper. The theoretical solution is verified by the field test，and the results show that the presented methods predicted accurately the load-settlement relationship of the new and old piles.
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2016, Vol. 35 
