Reliability assessment of a beam according to SBRA

Reliability assessment of a beam according to SBRA method and Eurocode David Pustka VŠB – Technical University of Ostrava Faculty of Civil Engineering Ludvíka Podéště 1875, 708 00 Ostrava, Czech Republic

Introduction In the last year was performed the study comparing the reliability assessment according to EUROCODE and SBRA method. Among to significant differences in these two approaches belongs maximum load effects determination: In the EUROCODE the maximum load effects determination is based on evaluation of individual load situations constructed using combination formulas. The SBRA method allows to direct calculate the maximum load effect due to direct Monte Carlo simulation technique.

Example assignment Simply supported steel beam with overhanging end:

Load effects calculation Shear forces development along the beam length – EUROCODE vs. SBRA

Load effects calculation Bending moments development along the beam length – EUROCODE vs. SBRA

Load effects calculation Vertical deflections development along the beam length – EUROCODE vs. SBRA

Reliability assessment The reliability assessment according to EUROCODE is based on comparison of resistance R and load effect S. S<R The reliability assessment according to the SBRA method is based on checking of reliability criterion: Pf < P d where Pd is target probability given in code and Pf is probability of failure calculated from corresponding reliability function.

Summary and conclusions The reliability assessment according to the EUROCODE ( based on partial factor design) is laborious, cloudly and leads to non-balanced reliability level. The SBRA method offers possibility simply and clearly assess the reliability of structure and to reach balanced level of reliability.

Thank you for attention …
- Slides: 9