Model test study of anti-pulling property of X-shaped concrete pile

Comparative test study of anti-pulling property of X-shaped pile and circular section pile with constant section is carried out in the self-developed large-scale soil test model chamber.The distributions of axial forces,lateral frictions and displacement are analyzed.the lateral surface of The X-shaped pile is 31.5% greater than the circular section pile;but the distributions of lateral friction force along pile shaft are almost the same,which consist of two different zones,raising zone and decay zone.The friction force is fully exerted from 1.5 m to 3 m away the pile head,and the minimum value and peak value of X-shaped pile in the area are larger than circular section pile.Under the same settlements,the lateral friction force of X-shaped pile is greater than circular pile.The results show that the ability of X-shaped pile to resist uplift force is 16.7% higher than that of the circular pile.