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http://dx.doi.org/10.7843/kgs.2010.26.8.27

A Comparison of Bearing Capacity Equations for a Single Pile Considering Negative Skin Friction  

Lee, Sung-June (Dept. of Civil Engrg., Yonsei Univ.)
Jeong, Sang-Seom (Dept. of Civil Engrg., Yonsei Univ.)
Ko, Jun-Young (Dept. of Civil Engrg., Yonsei Univ.)
Publication Information
Journal of the Korean Geotechnical Society / v.26, no.8, 2010 , pp. 27-37 More about this Journal
Abstract
Downdrag force develops when a pile is driven through a soil layer which will settle more than a pile. There is no obvious criterion for application of the current pile design method considering the negative skin friction. Therefore, in this study, numerical analyses were performed to investigate the behavior of a single pile subjected to negative skin friction and their results were used to determine the applicability of the current design method. Including three different sites in Song-do area and two different cases with friction pile and end bearing pile conditions, total six cases were considered. The load-settlement relationships and the neutral points were estimated for different end bearing conditions and the allowable bearing capacity of piles with negative skin friction was investigated through parametric studies. Based on the results showed that the negative skin friction made a major influence on the settlement of a pile and its stress. However the allowable bearing capacity may not be influenced by the negative skin friction. Compared with the allowable bearing capacity obtained from the ultimate bearing capacity with the safety factor of 3, the current design method with the safety factor of 3 underestimated the allowable bearing capacities regardless of the end bearing conditions. On the other hand, the current design method with the safety factor of 2 yielded reasonable results depending on the end bearing conditions.
Keywords
Bearing capacity; End bearing; Friction; Negative skin friction; Neutral point; Settlement;
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  • Reference
1 Federal Highway Administration (1996), Design and Construction of Driven Pile Foundations, Publication No. FHWA-HI-96-033, Chapter 9, pp.136-140.
2 Fellenius, B. H. (1972), "Downdrag on Piles in Clay due to Negative Skin Friction", Canadian Geotechnical Journal, Vol.9, No.4, pp.323-337.   DOI
3 Fellenius, B. H. (1989), "Unified design of piles and pile groups", Transportation Research Board 1169, pp.75-81.
4 Jeong, S. S., Kim, S. I., and Briuad, J. L. (1997), "Analysis of Downdrag on Pile Groups by the Finite Element Method", Computers and Geotechnics, Vol.21, No.2, pp.143-161.   DOI   ScienceOn
5 US Army Corps of Engineer (1991), Design of Pile Foundations, Engineer Manual No. 1110-2-2906, pp.42-45.
6 Astralian Standard (1995), Piling-Design and Installation, the Standards Australia Committee CE/18 on Piling, AS 2159, pp.16-21.
7 Briaud, J. L. and Tucker, L. M. (1996), Design and Construction Guidelines for Downdrag on Uncoated and Bitumen-coated Piles, National Cooperative Highway Research Program Transportation Research Board, 198p.
8 김준수, 정상섬 (1996), "부주면마찰력을 고려한 단독말뚝의 지지력 산정", KSG Spring National Conference, pp.337-344.
9 Canadian Foundation Engineering Manual, CFEM (1992), Third Edition. Canadian Geotechnical Society, BiTech publishers, Cancouver, 512p.
10 Geo Publication (2006), Foundation Design and Construction, Geotechnical Engineering Office, The Goverment of the Hong Kong, pp.131-135.
11 한국지반공학회 (1997), 개선된 강관말뚝의 설계와 시공.
12 정상섬 (2001), "말뚝의 부주면마찰력 산정 및 허용하중결정", 한국지반공학회 2001 현장기술자를 위한 말뚝기초워크샵, pp.76-89.
13 정상섬 (2003), "하향력을 받는 군말뚝의 3차원 수치해석", 한국지반공학회 2003 현장기술자를 위한 말뚝기초워크샵, pp.39-56.
14 포스코개발주식회사 (1998), 포항 LNG 발전소 말뚝재하시험보고서, POSCO.
15 한국지반공학회 (2009), 구조물 기초 설계기준해설.
16 경성대학교 공학기술연구소 (2001), 부산강서경기장 건립공사의 부마찰력 확인을 위한 현장시험 연구용역 보고서, 경성대학교.