Reliability Analysis

For reliability analysis, optiSLang provides powerful numerical algorithms for the determination of small event violation probabilities. Thus, it allows the essential final verification of such failure scenarios subsequent to a robustness evaluation or Robust Design Optimizations (RDO).

Best Practice

  • Robustness evaluation for the approximation of violation probabilities and for the identification of important random variables as the basis for an appropriate selection of methods regarding a reliability analysis
  • Definition of one or various failure mechanisms using limit state functions
  • Recommendation of verifying low probabilities of failure with two alternative algorithms of reliability analysis


  • First Order Reliability Method (FORM) and Adaptive Importance Sampling for continuously differentiable limit state functions
  • Directional Sampling and Adaptive Sampling (AS) for a moderate number of random variables, multiple failure mechanisms and small probabilities of failure
  • Adaptive Response Surface Method (ARSM) as the most efficient method for up to 15 important random variables

Postprocessing & Visualization

  • Histograms
  • 2D/3D anthill plots
  • History plots
  • Violation probabilities


optiSLang is sold worldwide. A list of our distributors can be found here.

Your contact person

Dr.-Ing. Johannes Will

Fon: +49 (0) 3643 9008-30
Fax: +49 (0) 3643 9008-39