Model Test Research on Mechanism of Close-Ended Variable Section Pipe Pile

Abstract:

Base on indoor model experiments of two constant section pipe piles and three variable section pipe piles performed in foundation pit,the load transfer mechanism of two kinds of close-ended pipe piles are studied by comparing load-settlement curves,shaft load distribution behaviors,skin resistance and resistance on pile end.Results show bearing capacity of variable section pipe piles is bigger than constant section pipe piles when settlements on pile top are equal.The bearing vertical capacity, unit volume bearing vertical capacity and availability of material of pipe pile will increase with improvement of average diameter and variable section ratio of variable section pipe piles.To variable section pipe pile, shaft load distribution suffered a sudden drop on position of variable section and shaft load distribution of small diameter pipe piles decrease quickly than constant section pipe piles.Resistance on pile end of variable section pipe piles are bigger than constant section pipe piles and resistance, ratio of resistance on pile end to bearing capacity of variable section pipe piles will increase with improvement of average diameter of variable section pipe pile. Action point of max skin resistance of variable section pipe piles are closer to pile top than constant section pipe piles .Max skin resistance will increase with decline with ratio of variable section pipe pile.If settlements on pile top are equal,force of skin resistance of variable section pipe piles are bigger than constant section pipe piles when the average diameters are same.

• Periodical: Applied Mechanics and Materials (Volumes 638-640)
• Pages: 480-484
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.638-640.480
• Online since: September 2014
• Authors: Qing Guang Yang*, Ya Hui Wang, Feng Liu, Jie Liu
• Keywords: Mechanism, Pile End Resistance, Skin Resistance, Variable Section Pipe Pile

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