The increase in capacity of displacement piles with time after installation is typically known as soil/pile set-up. A full-scale field test is carried out to observe the set-up effect for open-ended concrete pipe pile...The increase in capacity of displacement piles with time after installation is typically known as soil/pile set-up. A full-scale field test is carried out to observe the set-up effect for open-ended concrete pipe piles jacked into mixed soils. Both the total capacity and the average unit shaft resistance increase approximately linearly with logarithmic time. The average increase rate for unit shaft resistance is 44% per log cycle, while the average increase for total capacity is approximately 21%. A review on case histories for long-term set-up indicates an average set-up rate of approximately 40%. Based on this, the mechanism of pile set-up is discussed in detail and a three-phase model is suggested.展开更多
基金Project supported by the National Natural Science Foundation of China (No. 51078330)the Natural Science Foundation of Zhejiang Province (No. Y1090610),China
文摘The increase in capacity of displacement piles with time after installation is typically known as soil/pile set-up. A full-scale field test is carried out to observe the set-up effect for open-ended concrete pipe piles jacked into mixed soils. Both the total capacity and the average unit shaft resistance increase approximately linearly with logarithmic time. The average increase rate for unit shaft resistance is 44% per log cycle, while the average increase for total capacity is approximately 21%. A review on case histories for long-term set-up indicates an average set-up rate of approximately 40%. Based on this, the mechanism of pile set-up is discussed in detail and a three-phase model is suggested.