Comparison of Lateral Pile Behavior under Static and Dynamic Loading by Centrifuge Tests

Min-Taek Yoo; Sun-Yong Kwon

doi:10.7843/kgs.2018.34.7.51

All Issue

2018 Vol.34, Issue 7 Preview Page

Research Article

Comparison of Lateral Pile Behavior under Static and Dynamic Loading by Centrifuge Tests 원심모형 실험을 이용한 지반-말뚝 상호작용의 정적 및 동적 거동 평가

31 July 2018. pp. 51-58

PDF XML

Abstract

In this study a series of centrifuge tests were carried out in dry sand to analyze the comparison of lateral pile behavior for static loading and dynamic loading condition. In case of static loading condition, the lateral displacement was applied up to 50% of pile diameter by deflection control method. And the input sine wave of 0.1 g～0.4 g amplitude and 1 Hz frequency was applied at the base of the soil box using shaking table for dynamic loading condition. From comparison of experimental static p-y curve obtained from static loading tests with API p-y curves, API p-y curves can predict well within 20% error the ultimate subgrade reaction force of static loading condition. The ultimate subgrade reaction force of experimental dynamic p-y curve is 5 times larger than that of API p-y curves and experimental static p-y curves. Therefore, pseudo-static analysis applied to existing p-y curve for seismic design could greatly underestimate the soil resistance at non-linear domain and cause overly conservative design.

Keywords

Centrifuge test

Soil-structure-interaction

Dynamic p-y curve

Static p-y curve

API p-y curve

본 연구에서는 하중 조건에 따른 지반-말뚝 상호작용 시스템의 거동 차이를 분석하기 위해 일련의 원심모형 실험을 수행하였다. 정적 하중 조건의 경우, 말뚝 직경의 50% 수준까지 변위제어를 통해 하중을 재하하였으며, 지진 하중 조건의 경우 0.1g～0.4g 수준으로 1Hz 정현파를 가진하였다. 실험 결과로부터 얻은 정적 및 동적 p-y 곡선을 API p-y 곡선과 비교한 결과, API p-y 곡선과 정적 하중조건에서의 실험 p-y 곡선은 최대 지반반력 값이 20% 이내의 오차를 보인 반면, 동적 하중 조건에서의 실험 p-y 곡선과는 최대 지반반력 값이 5배 이상 차이가 발생하였다. 이는 등가정적 해석에서 기존 API p-y 곡선을 적용할 경우 비선형 영역에서 지반 반력을 크게 과소평가하며 보수적 설계를 야기할 수 있음을 의미한다.

References

American Petroleum Institute (API) (1987), “Recommended Practice for Planning, Designing and Constructing Fixed Offshore Platforms”, API Recommendation Practice 2A (RP 2A), 17th edition.

???

Dou, H. and Byrne, P.M. (1996), “Dynamic Response of Single Piles and Soil-pile Interaction”, Canadian Geotechnical Journal, Vol.33, No.1, pp.80-96.

10.1139/t96-025

Kondner, R.L. (1963), “Hyperbolic Stress-strain Response:Cohesive Soils”, J. Soil Mechanics and Foundation Div., ASCE, Vol.87, No.1, pp.115-144.

???

Korean Society of Civil Engineers (KSCE) (2001), “Bridge Design Criteria of Korea”.

???

National Cooperative Highway Research Program (NCHRP) (2001), “Static and Dynamic Lateral Loading of Pile Groups, NCHRP Report 461”, Transportation Research Board - National Research Council., pp.13-21.

???

Ovesen, N. K. (1979), “The Scaling Law Relationship”, Proceedings of the 7th European Conference on Soil Mechanics and Foundation Engineering, Brighton, Vol.4, pp.319-323.

???

Ting, J.M., Kauffman, C.R., and Lovicsek, M. (1987), “Centrifuge Static and Dynamic Lateral Pile behaviour”, Canadian Geotechnical Journal, Vol.24, pp.198-207.

10.1139/t87-025

Yang, E.K., Jeong, S.S., Kim. J.H., and Kim, M.M. (2011), “Dynamic p-y Backbone Curves from 1g Shaking Table Tests”, KSCE Journal of Civil Engineering, Vol.15, No.5, pp.813-821.

10.1007/s12205-011-1113-0

Yoo, M.T., Choi, J.I., Han, J.T., and Kim, M.M. (2013), Dynamic p-y Curves for Dry Sand from Centrifuge Tests, Journal of Earthquake Engineering, Vol.17, Issue 7, pp.1082-1102.

10.1080/13632469.2013.801377

Information

Publisher :The Korean Geotechnical Society
Publisher(Ko) :한국지반공학회
Journal Title :Journal of the Korean Geotechnical Society
Journal Title(Ko) :한국지반공학회 논문집
Volume : 34
No :7
Pages :51-58
Received Date : 2018-06-04
Revised Date : 2018-06-22
Accepted Date : 2018-06-25
DOI :https://doi.org/10.7843/kgs.2018.34.7.51

Journal of the Korean Geotechnical Society ISSN:1229-2427(Print) 2288-646X(Online) 한국지반공학회 논문집

All Issue