Semi-probabilistic approaches for action effects

Abstract

: The computational burden of Monte Carlo (MC) type simulation represents the main obstacle to the approach for time-consuming finite element (FE) computational models since it is not computationally feasible. Consideration of uncertainties, therefore, remains usually at the level of partial safety factors, the approach which is in most cases on the very conservative side. That is why alternative techniques of so-called safety formats are becoming more and more attractive recently. Methods focused on the Estimation of Coefficient of Variation (ECoV) of structural resistance have been developed and applied recently. They represent a compromise between the simple and in most cases conservative approach of partial safety factors and highly computationally demanding MC simulation. Semi-probabilistic methods have been applied for structural resistance assessment, but not for the action effects side. The paper shows the possibility of application of these methods for action effect – load side of safety margin. Selected efficient semi-probabilistic methods based on the ECoV method according to fib Model Code 2010 and an improved approach called Eigen ECoV, are utilized. The application of approaches for the assessment of concrete tunnel linings is shown.