قارن الطرق

	طريقة الموثوقية من الدرجة الأولى (FORM)	طريقة الموثوقية من الرتبة الثانية (SORM)
المجال	هندسة الموثوقية	هندسة الموثوقية
العائلة	Process / pipeline	Process / pipeline
سنة النشأة	1969	1979
صاحب الطريقة	Allin Cornell	Bernd Fiessler
النوع	Reliability analysis method	Reliability analysis method
المصدر التأسيسي	Cornell, C. A. (1969). A probability-based structural code. Journal of the American Concrete Institute, 66(12), 974-985.	Fiessler, B., Neumann, H. J., & Rackwitz, R. (1979). Quadratic limit states in structural reliability. Journal of the Engineering Mechanics Division, 105(4), 661-676.
الأسماء البديلة	FORM, First-order second-moment method	SORM, Second-order approximation
ذات صلة	4	4
الملخص	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.	The Second-Order Reliability Method (SORM) is an extension of FORM that improves failure probability estimates by accounting for the curvature of the limit-state surface at the design point. Introduced by Fiessler, Neumann, and Rackwitz in 1979, SORM provides more accurate approximations for nonlinear failure surfaces while remaining computationally efficient. It has become the standard refinement when FORM accuracy is insufficient.