Adaptive Importance Latin Hypercube Sampling
Probabilistic methods currently require many function evaluations or do not provide a mathematically robust confidence interval. The proposed method searches to find the Most Probable Point (MPP) using a Hasofer-Lind-Rackwitz-Fiessler (HLRF) algorithm, and then estimates reliability with Latin Hypercube Sampling (LHS) evaluating only those points outside of the MPP. Repeated samples provide several estimates of the reliability, which are aggregated to find a reliability estimate with a confidence interval. The computational efficiency is much better than standard LHS sampling and improves as the failure probability decreases. The method is applied to two example problems, each showing a statistically significant reduced confidence interval.