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Load Sharing Analysis of Piled Rafts Based on Non-linear Load-Settlement Characteristics

Piled Raft 기초의 비선형 하중-침하 특성을 고려한 하중분담 해석

  • Choi, Kyu-Jin (School of Civil and Environmental Eng., Yonsei Univ.) ;
  • Park, Dong-Gyu (School of Civil and Environmental Eng., Yonsei Univ.) ;
  • Lee, Jun-Hwan (School of Civil and Environmental Eng., Yonsei Univ.)
  • 최규진 (연세대학교 토목환경공학과) ;
  • 박동규 (연세대학교 토목환경공학과) ;
  • 이준환 (연세대학교 토목환경공학과)
  • Received : 2012.03.09
  • Accepted : 2012.11.20
  • Published : 2012.11.28

Abstract

The design of Piled Raft foundations considering the load sharing between raft and piles provides a more economical solution than the conventional design approach based on bearing capacity of piles only. Generally, numerical methods are used to analyze the behavior of Piled Rafts due to its complexity and load sharing ratio is also estimated by numerical methods about some limited cases under specific load level and soil conditions. In this study, a method to estimate the load sharing between the raft and piles was developed which is based on load-settlement characteristics of foundation elements. Normalized load-settlement curves of the raft and pile groups were derived individually, and the relationship between load sharing ratio and foundation settlement was proposed by using these curves. For each load-settlement curves, hyperbolic type was adopted in order to describe the non-linear behavior of foundations. Centrifuge test results were compared with the results from proposed method, and the trends of variation of load sharing ratio with settlement presented from both were similar.

Keywords

Piled Rafts;Load sharing;Load-settlement;Hyperbolic curve

Acknowledgement

Grant : 기후변화 적응형 지반구조물 설계 기술 개발

Supported by : 한국과학재단

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