Structural Engineering and Mechanics

  • 제7권6호
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  • Pages.533-550
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  • 1999
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  • 1225-4568(pISSN)
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  • 1598-6217(eISSN)
테크노프레스 (Techno-Press)
권호 표지
DOI QR코드

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Optimization approach applied to nonlinear analysis of raft-pile foundations

  • Tandjiria, V. (School of Civil Engineering, University of New South Wales) ;
  • Valliappan, S. (School of Civil Engineering, University of New South Wales) ;
  • Khalili, N. (School of Civil Engineering, University of New South Wales)
  • 발행 : 1999.06.25
⟨ 이전 논문 다음 논문 ⟩

초록

Optimal design of raft-pile foundations is examined by combining finite element technique and the optimization approach. The piles and soil medium are modeled by three dimensional solid elements while the raft is modelled by shell elements. Drucker-Prager criterion is adopted for the soil medium while the raft and the piles are assumed to be linear elastic. For the optimization process, the approximate semi-analytical method is used for calculating constraint sensitivities and a constraint approximation method which is a combination of the extended Bi-point approximation and Lagrangian polynomial approximation is used for predicting the behaviour of the constraints. The objective function of the problem is the volume of materials of the foundation while the design variables are raft thickness, pile length and pile spacing. The generalized reduced gradient algorithm is chosen for solving the optimization process. It is demonstrated that the method proposed in this study is promising for obtaining optimal design of raft-pile foundations without carrying out a large number of analyses. The results are also compared with those obtained from the previous study in which linear analysis was carried out.

키워드

참고문헌

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