Abstract
The soil displacement field around a drill-expanded concrete pile is noticeably different from that of an equivalent section pile placed under axial load due to the mutual embedment between the expanded body and the soil. It is important to study the soil displacement field around drill-expanded concrete piles in order to understand the mechanisms of interaction between the pile and the soil. First, the model test of the half-face pile installed in undisturbed soil and the model test of the half-face pile installed in sand were used to study the soil displacement field around the pile. Then, the entire process of the soil displacement field’s formation and development under the load was observed by using digital image correlation (DIC) techniques. Finally, numerical simulation was used to verify the results of the model tests. The results show that the displacement characteristics of the soil around the pile in the undisturbed soil and sand are basically the same. There is a clear soil compression zone under the expanded body, and the magnitude and density of the displaced soil in the compression zone are much higher than in other areas. Both the vertical displacement and the horizontal displacement gradually decrease as the distance from the expanded body and the burial depth increase. The horizontal displacement of the soil under the expanded body follows a trend of first moving toward the pile body and then moving away from it. The results of the numerical simulation are basically consistent with the results of the model test, indicating that the results of the model test are relatively reliable.
Highlights
The drill-expanded concrete pile is a new type of variable cross-section cast-in-place pile based on the expanded pile and which has one or more expanded bodies at the appropriate positions based on the ordinary straight-hole cast-in-place pile created by drilling and expanding equipment
When drilling to the specified position, the equipment is reversed to start the diameter expansion, and the drilling-expanding arm gradually expands to cut the soil around the hole wall (Figure 1b)
The equipment is switched to drilling mode, after which the diameter expansion is carried out
Summary
The drill-expanded concrete pile is a new type of variable cross-section cast-in-place pile based on the expanded pile and which has one or more expanded bodies at the appropriate positions based on the ordinary straight-hole cast-in-place pile created by drilling and expanding equipment. Compared with regular expanded piles, drill-expanded concrete piles have better pile quality and less disturbance of the soil around the pile due to the difference in construction technology. The forward rotation is used to start drilling (Figure 1a). When drilling to the specified position, the equipment is reversed to start the diameter expansion, and the drilling-expanding arm gradually expands to cut the soil around the hole wall (Figure 1b). Studying the process of soil displacement around the drill-expanded concrete pile is
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
