Strengthening mechanism of plum blossom pile composite foundation

• Published in: Acta geotechnica 2024-07, Vol.19 (7), p.4791-4808
• Main Authors: Li, Long, Deng, You-sheng
• Format: Article
• Language: English
• Subjects: Bearing capacity; Cast in place; Civil engineering; Compaction; Complex Fluids and Microfluidics; Deformation; Engineering; Field study; Foundations; Geoengineering; Geotechnical engineering; Geotechnical Engineering & Applied Earth Sciences; Hydraulics; Infinite elements; Investigations; Laboratories; Load; Mineral oils; Pile bearing capacities; Piles; Quartz; Research Paper; Sensors; Soft and Granular Matter; Software; Software engineering; Soil; Soil analysis; Soil bearing capacity; Soil compaction; Soil penetration tests; Soil Science & Conservation; Soil stresses; Soil testing; Soils; Solid Mechanics; Strengthening; Transition zone; Vertical loads; Vertical penetration
• ISSN: 1861-1125; 1861-1133
• DOI: 10.1007/s11440-023-02208-5

Previous studies found that the strengthening mechanism of piles in composite foundation is related to the cross sectional shape of piles. However, the mechanism of plum blossom cast-in-place pile (plum blossom pile), as a novel kind of pile, strengthening mechanism is still unclear. In the present study, based on the transparent soil model test technique and Coupled Eulerian–Lagrangian (CEL) approach, single pile penetration tests were conducted. The load-vertical displacement characteristics of composite foundation and the variation of soil around piles are analyzed, and compared with circular piles with same cross sectional area. The results show that the ultimate bearing capacity of plum blossom pile is 1.45 times that of circular pile with the same cross sectional area. The compaction transition zone is observed in the soil around the plum blossom pile during the penetration process, and the radial distance of the compaction transition zone around the plum blossom pile is about 1.5 times that of the circular pile with the same cross sectional area. With the help of geotechnical engineering infinite element software Abaqus/Explicit, the variation of the mean pressure, radial stress and vertical stress of the soil around the plum blossom pile, and the evolution of the compaction transition zone and stress of soil around the pile are analyzed. With the penetration of plum blossom pile, the compaction transition zone at the pile side gradually increases, and the load can be transferred to a wider range in the composite foundation through the pile side compacting the soil around the pile. The research results can provide technical guidance for the design of the plum blossom pile composite foundation.