New Hybrid Convex Model and Probability Reliability Method for Structures

The reliability assessment of structures with partial statistic information is investigated by establishing a general hybrid convex model and probability reliability model.A general non-probabilistic reliability model for structures is proposed based on the info-gap(information gap) theory.A special ellipsoidal-bound non-probabilistic structural reliability model equaling to probabilistic reliability model is established.The hybrid reliability problem exhibiting both convex model and probabilistic uncertainties is transformed into a non-probabilistic one by applying a special ellipsoidal-bound convex model to describe stochastic variables.Then a new general hybrid convex model and probability reliability model for structures is proposed based on the non-probabilistic reliability model.The hybrid reliability index has both robust and probabilistic reliability meanings and can be obtained by solving an optimization problem.The numerical examples prove that the previous hybrid reliability method can not work properly when the degree of uncertainty of the data is high or low and the new method has superiority and more rationality.