Process / pipelineProbabilistic safety analysis

First-Order Reliability Method (FORM)

The First-Order Reliability Method (FORM) is a probabilistic technique for estimating the probability of structural failure given uncertain input parameters. Developed by Allin Cornell in 1969 and refined by Hasofer and Lind in 1974, FORM provides a computationally efficient approximation to the true failure probability by linearizing the limit-state function at the most probable failure point. It has become the cornerstone of modern structural reliability analysis and risk-based design.

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Sources

  1. Cornell, C. A. (1969). A probability-based structural code. Journal of the American Concrete Institute, 66(12), 974-985. DOI: 10.14359/7446
  2. Hasofer, A. M., & Lind, N. C. (1974). Exact and invariant second-moment code format. Journal of the Engineering Mechanics Division, 100(1), 111-121. DOI: 10.1061/jmcea3.0001892
  3. Rackwitz, R., & Fiessler, B. (1978). Structural reliability under combined random load sequences. Computers & Structures, 9(5), 489-494. DOI: 10.1016/0045-7949(78)90046-9
  4. Melchers, R. E. (2002). Structural Reliability Analysis and Prediction (2nd ed.). John Wiley & Sons. DOI: 10.1002/9780470869970

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Referenced by

ScholarGateFirst-Order Reliability Method (First-Order Reliability Method (FORM)). Retrieved 2026-06-04 from https://scholargate.app/en/reliability-engineering/first-order-reliability-method