r - The Hong Kong Polytechnic University

Figure 3 Physical diagrams of pile head of XCC pile, and circular pile
Table 2 Parameters of test piles
Parameters XCC C 1 C 2
Area /m 2 0.1425 0.1425 0.2462
Perimeter /m 1.7604 1.3401 1.7604
Square side length /m 0.5303 - -
Arc space /m 0.11 - -
Radian /° 90 - -
Diameter /m - 0.426 0.560
Pile length /m 5.0 5.0 5.0
Model Soils
Test soil is divided into two layers. The upper 2.4 m layer is sand. In order to ensure density coherency, fall sand
height should be controlled and each layer should be flat compaction. The lower 3.9 m layer is salty clay. The
soil is approximately homogeneous materials. Indoor geotechnical test is performed before filling soil, and soil
specific parameters are shown in Table 1. Especially, the dry density is controlled during the whole filling
process.
Material
RESULTS AND DISCUSSIONS
Axial Compression Load Test
Table 1 Mechanical parameter of soils
Cohesion
c /kPa
Friction
angle φ /°
Water ratio
ω /%
Nature
density
ρ /g/cm 3
Sand 17.6 25.9 5.1 1.5
Clay 27.6 21.2 16.7 1.9
In Figure 5, base on the China Pile Foundation Construction Technical Specification (JGJ94-2008) of the ultimate
bearing capacity judgment method, it is to know that the ultimate bearing capacity of XCC pile equals 119 kN,
limit bearing capacities of circular pile C 1 and C 2 equal 90 kN, 140 kN, respectively. Compared with the circular
pile C 1 in the same area, the concrete consumption of the XCC pile is the same with that of C 1 , its perimeter is 1.31
times that of C 1 , and its ultimate bearing capacity 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 . Although the ultimate bearing capacity of the XCC pile is on higher than
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