Uplift behavior and load transfer mechanism of prestressed high-strength concrete piles

Abstract

Prestressed high-strength-concrete (PHC) tube-shaped pile is one of the recently used foundations for soft soil. The research on uplift resistance of PHC pile is helpful to the design of pile foundations. A field-scale test program was conducted to study the uplift behavior and load transfer mechanism of PHC piles in soft soil. The pullout load tests were divided into two groups with different diameters, and there were three piles in each group. A detailed discussion of the axial load transfer and pile skin resistance distribution was also included. It is found from the tests that the uplift capacity increases with increasing the diameter of pile. When the diameter of piles increases from 500 to 600 mm, the uplift load is increased by 51.2%. According to the load−displacement (Q−S) curves, all the piles do not reach the ultimate state at the maximum load. The experimental results show that the piles still have uplift bearing capacity.

Exploration of the slope effect on the uplift capacity of single straight and belled piles supporting transmission towers

“…Shin et al (1993) experimentally evaluated the uplift capacity of rigid piles embedded in a compacted near-saturated clayey soil. Lai and Jin (2010) carried out a field-scale model test to investigate the load transfer mechanism of PHC piles in soft soil under uplift loading. However, little research is conducted to investigate the uplift behavior of piles embedded in the mountain areas, where the ground frequently consists of not only clay or sand but also weathered rocks.…”