Bearing Deformation Mechanism of CFG Pile Composite Foundation Under High Stress(PDF)
《建筑科学与工程学报》[ISSN:1673-2049/CN:61-1442/TU]
- Issue:
- 2018年04期
- Page:
- 81-88
- Research Field:
- Publishing date:
Info
- Title:
- Bearing Deformation Mechanism of CFG Pile Composite Foundation Under High Stress
- Author(s):
- ZHI Bin; WU-LI He-le; WANG Pan; WANG Yong-xin; LI Ge
- School of Architecture and Civil Engineering, Xi’an University of Science and Technology
- Keywords:
- CFG pile composite foundation; high stress test; cushion; pile-soil stress ratio
- PACS:
- -
- DOI:
- -
- Abstract:
- In order to explore the deformation mechanism of cement fly-ash gravel pile (CFG pile) composite foundation under high stress, the numerical model of CFG pile composite foundation was established and analyzed based on the high stress test of planning site in Xian high-tech zone. The results show that the ultimate bearing capacity of CFG pile composite foundation in the site is not less than 1 720 kPa. The cushion layer is damaged under high stress, and the coordination ability about combined action of pile and soil is reduced. The pile top is thrust upward into the cushion layer, and the load is concentrated to the pile top, which causes the pile to bear 96.5% of the upper load. The capacity of soil between the piles is limited, and the composite foundation is equivalent to the single pile bearing. The cushion thickness is negatively correlated with the increase of pile-soil stress ratio. The settlement difference between soil and pile top increases with the increase of load, and the settlement difference increases firstly and then decreases with the increase of cushion thickness. When the bearing capacity of single pile meets the requirements, in order to ensure that the soil between piles under high stress is not damaged due to overloading, the cushion thickness should be reduced and the flow compensation ability should be reduced. The conclusion can provide reference for the design of CFG pile composite foundation in the foundation treatment of high-rise buildings.
Last Update: 2018-07-18