Updating reliability models of statically loaded instrumented structures

The study extends the first order reliability method (FORM) and inverse FORM to update reliability models for existing, statically loaded structures based on measured responses. Solutions based on Bayes’ theorem, Markov chain Monte Carlo simulations, and inverse reliability analysis are developed. The case of linear systems with Gaussian uncertainties and linear performance functions is shown to be exactly solvable. FORM and inverse reliability based methods are subsequently developed to deal with more general problems. The proposed procedures are implemented by combining Matlab based reliability modules with finite element models residing on the Abaqus software. Numerical illustrations on linear and nonlinear frames are presented.

▸ Updating of reliability index and safety margin based on measured response. ▸ Updating of design point and sensitivity vector. ▸ Combined system identification and reliability model updating. ▸ Exact solutions for a class of problems. ▸ Nonlinear structural and measurement models, and non-normal uncertainties.