Characteristics of Skin Friction on Compression Loaded Group Piles

압축하중을 받는 무리말뚝의 주면지지력 특성

  • Ahn Byung-Chul (Department of Civil Engineering, Chungbuk National University) ;
  • Lee Jun-Dae (Department of Civil Engineering, Chungbuk National University)
  • 안병철 (충북대학교 토목공학과) ;
  • 이준대 (세명대학교 토목공학과)
  • Published : 2004.09.01

Abstract

H-pile can be more easily driven than pipe pile by pile driver and shows high skin friction and plugging effect. And lately It is well grown that the high strength H-pile has been widely used f3r pile foundations. To compare the skin frictions of H piles under different density soil conditions, this paper presents results of a series of model tests on vertically loaded group piles. Model piles made of steel embedded in weathered granite soil were used in this study. Pile arrangements $(2\times2,\;3\tunes3)$, pile space(2D, 4D, 6D), and soil density$(D_r=40\%,\;80\%)$ were tested. The main results obtained from the model tests can be summarized as follows. The series of tests found that compression load for group piles increases as number of piles increase and piles space ratic decrease to $D_r=40\%$ of soil density. The analysis also found that the theoretical value of skin friction for group piles is greater than practical value as piles space ratio increases to $D_r=40\%$ of soil density. Piles showed the greatest difference of the skin friction in case that the pile space ratio(S/D) is 6. The theoretical value by Meyerhof and DM-7 showed 1.83 times and 1.32 times respectively as great as practical value in case of S/D=6 and $2\times2$.

Keywords

References

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