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Proceedings of the 18
th
International Conference on Soil Mechanics and Geotechnical Engineering, Paris 2013
the load shared by the soil, so the differential settlement is
increscent. Because the compressibility of the soil is far greater
than the pile, the settlement of the soil is far larger than the pile,
as a result, the displacement of the soil is downward with
respect to the pile and the downdrag is generated, that is the
negative friction. The larger the load pressure, the greater the
negative friction. The results in Fig. 4 also show that the
location of neutral points is about -2 m, which is almost
unchanged as the increase of the load.
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6 SUMMARY AND CONCLUSIONS
Based on large-scale load tests and field test of a XCC pile
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(1) Regarding the contact area of pile-soil interface and EI of
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7 ACKNOWLEDGEMENTS
The authors acknowledge the financial support from the
National Science Joint High Speed Railway Foundation of
China (No. U1134207), and the National Science Foundation of
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