r - The Hong Kong Polytechnic University

load-deflection curve at the pile head. Therefore, for the same lateral capacity, the amount of concrete volume
used in a XCC pile is about 6.9 % less than in a circular pile.
CONCLUSIONS
Lateral displacement of pile head, y 0
(mm)
0 10 20 30 40 50 60
0
10
20
30
40
50
Pile head lateral load, H 0
(kN)
XCC pile
Circular pile
Figure 7 The curves of pile head lateral load versus displacement (H 0 -y 0 curves)
Based on the full-scale experimental study on the shape effects of cast-in-place concrete piles, the following
conclusions may be drawn. XCC pile has larger ultimate bearing capacity than circular pile with the same
concrete usage; In other words, XCC pile can save concrete usage under the same working load. The ultimate
compressive bearing capacity of XCC pile is 1.32 times that of C 1 , that is to say its ultimate bearing capacity
than that of the circular pile C 1 in the same area increases by 32 %. Compared with the circular pile C 2 in the
same perimeter, the concrete consumption of the XCC pile is only 0.58 times that of C 1 , while its ultimate
bearing capacity is 0.84 times that of C 2 . The ultimate uplift bearing capacity and lateral bearing capacity of
XCC pile is improved 25.8 %, and 6.9 %, respectively.
ACKNOWLEDGMENTS
The authors gratefully acknowledge the financial support provided by the National Science Foundation of China
(No. 51008116), the Provincial Science Foundation of Jiangsu, China (No. BK2008040), the Jiangsu
Postdoctoral Science Foundation Funded Project (No. 1001017B), and the Fundamental Research Funds for the
Central Universities (No. 2009B14514).
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