말뚝지지 전면기초의 설계를 위한 실용적 해석방법에 관한 연구 = A Practical Analysis Method for the Design of Piled Raft Foundations

다국어 초록 (Multilingual Abstract)

Piled raft foundations have been highlighted as an economical design concept of pile foundations in recent years. However, piled raft foundations have not been widely used in Korea due to the difficulty in estimating the complex interaction effects among rafts, piles and soils. The authors developed an effective numerical program to analyze the behavior of piled raft foundations for practical design purposes and presented it briefly in this paper. The developed numerical program simulates the raft as a flexible plate consisting of finite elements with eight nodes and the raft is supported by a series of elastic springs representing subsoils and piles. This study imported another model to simulate pile groups considering non-linear behavior and interaction effects. The apparent stiffnesses of the soils and piles were estimated by iterative calculations to satisfy the compatibility between those two components and the behavior of piled raft foundations can be predicted using these stiffnesses. For the verification of the program, the analysis results about some example problems were compared with those of rigorous three dimensional finite element analysis and other approximate analysis methods. It was found that the program can analyze non-linear behaviors and interaction effects efficiently in multi-layered soils and has sufficient capabilities for application to practical analysis and design of piled raft foundations.

참고문헌 (Reference)

1 현대건설 기술연구소, "무리말뚝 및 상부기초 통합 해석 시스템 개발" 현대건설 기술연구소 1999

2 현대건설 기술연구소, "말뚝지지 전면기초의 실용화에 관한 연구" 현대건설 기술연구소 2008

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