The first-order reliability method, (FORM), is a semi-probabilistic reliability analysis method devised to evaluate the reliability of a system. The accuracy of the method can be improved by averaging over many samples, which is known as Line Sampling.[1][2]
The method is also known as the Hasofer-Lind Reliability Index, developed by Professor Michael Hasofer and Professor Niels Lind in 1974.[3][4] The index has been recognized as an important step towards the development of contemporary methods to effectively and accurately estimate structural safety.[5][6]
The analysis method depends on a "Most Probable Point" on the limit state [7]
Hasofer, Abraham M., & Lind, Niels C. (1974). "An Exact and Invariant First Order Reliability Format." ASCE Journal of the Engineering Mechanics Division. Vol. 100. EM1. Feb 1974. 111-121
Huang, Jinsong, and D. V. Griffiths. "Observations on FORM in a simple geomechanics example." Structural Safety 33, no. 1 (2011): 115-119.
Dudzik, A., and U. Radoń. "The reliability assessment for steel industrial building." Advances in Mechanics: Theorectical, Computational and Interdisciplinary Issues (2016): 163-166.
Choi, Chan Kyu, and Hong Hee Yoo. "Uncertainty analysis of nonlinear systems employing the first-order reliability method." Journal of Mechanical Science and Technology 26, no. 1 (2012): 39-44.