Integrated Reliability-Based Optimal Design of Structures

  • J. D. Sørensen
  • P. Thoft-Christensen
Conference paper
Part of the Lecture Notes in Engineering book series (LNENG, volume 33)


In conventional optimal design of structural systems the weight or the initial cost of the structure is usually used as objective function. Further, the constraints require that the stresses and/or strains at some critical points have to be less than some given values. Finally, all variables and parameters are assumed to be deterministic quantities. In this paper a probabilistic formulation is used. Some of the quantities specifying the load and the strength of the structure are modelled as random variables, and the constraints specify that the reliability of the structure has to exceed some given value. The reliability can be measured from an element and/or a systems point of view. A number of methods to solve reliability-based optimization problems has been suggested, see e.g. Frangopol [1], Murotsu et al. [2], Thoft-Christensen & Sørensen [3] and Sørensen [4].


Design Variable Reliability Index Safety Margin Inspection Quality Critical Crack Length 
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Copyright information

© Springer-Verlag Berlin, Heidelberg 1987

Authors and Affiliations

  • J. D. Sørensen
    • 1
  • P. Thoft-Christensen
    • 1
  1. 1.University of AalborgAalborgDenmark

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