DOI QR코드

DOI QR Code

수평재하에 따른 복합말뚝의 거동분석

Analysis of Composite Pile Behavior under Lateral Loadings

  • 황택진 (동의대학교 토목공학과)
  • 투고 : 2012.01.05
  • 심사 : 2012.03.08
  • 발행 : 2012.03.31

초록

복합말뚝은 서로 다른 재질을 사용하여 말뚝을 구성하는 말뚝으로 상부는 강관말뚝 하부는 콘크리트 말뚝으로 구성된 말뚝을 선 굴착 공법으로 시공하였다. 말뚝에는 7쌍의 변형률계와 경사계를 설치하여 말뚝의 수평재하시험 중 말뚝에 작용하는 응력과 변위를 측정하였다. 측정된 계측치는 여러 가지 이론적 공식을 이용하여 분석 비교하는 역 해석을 수행하였다. 분석결과 공식들로부터 예측한 말뚝에 작용하는 응력은 실제 측정된 값보다 크게 평가 되었으며, 말뚝상부에 응력이 크게 측정되다가 말뚝깊이에 따라 급격하게 감소하는 경향을 보였다. 측정된 응력은 모두 말뚝재질의 응력을 초과 하지 않아 복합말뚝의 설계개념을 검증할 수 있었다.

A composite pile consisted of a concrete lower part with a steel tubular pile at upper part was installed by pre-drilling method. Seven pairs of strain gauges and inclinometer were attached on the pile in order to measure stresses and displacement along the pile during the lateral loading test. The results of instrumentation were analyzed using various theoretical approaches. The back analysis showed that the measured stresses were smaller than those of the calculated. The maximum stress is measured at the steel upper part and decreased rapidly with depth of the pile. The calculated lateral displacement along the pile provide very good agreement with the measured values if the coefficient of subgrade reaction is selected properly. The design concept of a composite pile is verified by the measured stresses and displacement which is within the tolerable limits of the pile.

키워드

참고문헌

  1. Korea Society of Civil Engineers, Road Design Basis explanations, 2008.
  2. Korean Geotechnical Society, Foundation of Structure Design Basis, 2003.
  3. Ishida et al, "Static Horizontal Loading Test of Steel and Concrete Composite Pile Group", Summaries of Technical Papers of Annual Meeting Architectural Institute of Japan, Architectural Institute of Japan, 2002, pp.591-598
  4. Bhushan, K., Haley, S. C., and Fong, P. T., "Lateral Load Tests on Drilled Piers in stiff Clays", J. Geotech. Eng. Div. ASCE, Vol. 105, No. GT 8. August 1979, pp.969-985.
  5. Bowels, J.E., "Foundation analysis and design, 4th edition", McGraw Hill Book Company, New York,1988, pp.131-143.
  6. Brinch Hansen, J., "The Ultimate Resistance of Rigid Piles Against Transversal Forces", Danish Geotechnical Institute (Geoteknisk Institut) Bull. No.12, Copenhagen, 1961, pp.5-9
  7. Broms, B., "The Lateral Resistance of Piles in Cohesive Soils," J. Soil Mech. Found. Div., ASCE, Vol. 90, No. SM2, March 1964a, pp.27-63.
  8. Broms, B., "The Lateral Resistance of Piles in Cohesionless Soils," J. Soil Mech. Found. Div., ASCE, Vol. 90, No. SM3, May 1964b, pp.123-156
  9. FHWA, Manual on Design and Construction of Driven Pile Foundation, FHWA-DP-66-1, Federal Highway Administration, Washington, DC (available at the Construction Group Library), 1986.
  10. Hetenyi, M. Beams on Elastic Foundation. University of Michigan Press, Ann ARbor, 1946.
  11. Matlock, H. "correlations for Design of Laterally Loaded Piles in Soft Clay," Proceeding, Offshore Technology Conference, Houston, Texas, Paper No. 1204, 1970. pp. 557-594.
  12. Pando, M., Filz, G., Dove, J. and Hoppe, E., 2002, "Axial and Lateral Load Performance" TRB 82nd Annual Meeting in Janualry 2003 pp.61-70.
  13. Mindlin, R.D. "Force at a Pointin the Interior of a Semi-infinite Solid," physics, Vol. 7, No. 5, May, 1936, pp. 195-202 https://doi.org/10.1063/1.1745385
  14. NAVFAC Foundations and Earth Structures, Design Mannual 7.2, Department of the Navy, Alexandria, VA, May 1982.
  15. Poulos, H.G., "Behavior of Laterally Loaded Piles: I-Single Piles," J.Soil Mech. Found. Div., ASCE, Vol. 97 No. SM 5, 1971a, pp.711-731.
  16. Poulos, H.G., "Behavior of Laterally Loaded Piles: II-Pile Groups," J.Soil Mech. Found. Div., ASCE, Vol. 97 No. SM 5, 1971b, pp.733-751.
  17. Poulos, H.G., "Anaysis of Pile Groups Subjected to Vertical and Horizontal Loads," Augt. Geomechanics J., Vol., G4, No. 1, 1974, pp.26-32.
  18. Reese, L.C. and Matlock, H., "Non-dimensional Solutions for Laterally Loaded piles with Soil Modulus Assumed Proportional to Depth," Proceedings 8th Texas Conference on Soil Mechanics and Foundation Engineering, Austin, TX, 1957, pp.1-41.
  19. Reese, L.C., Cox, W.R., and Koch, F.D. "Analysis of Laterally Loaded Piles in Sand," Proceedings, VII Annual Offshore Technology Conference, Houston, TX, Vol. 2, Paper No. 2312, 1974, pp. 473-484.