Seismic Fragility Assessment of Local and Global Failures in Low-rise Non-ductile Existing RC Buildings: Empirical Shear-Axial Modelling vs. ASCE/SEI 41 Approach

Abstract

The brittle behavior of older non-ductile reinforced concrete buildings such as shear-axial failure in columns can cause lateral instability or gravity collapse. Hence, the attempt is to assess the collapse potential through fragility curves. Current research focuses on fragility assessment of these buildings emphasizing on shear-axial failure using two well-established methods; empirical limit state material versus ASCE/SEI 41-13 recommendations. To this aim, two 2D reinforced concrete models (3 and 5-story) according to typical detail of existing buildings in Iran were modeled using two aforementioned modeling approaches and analyzed under monotonic analysis and incremental dynamic analysis (IDA). In the following, seismic fragility assessment were carried out by means of obtained results from IDA. The results of fragility curves showed that, collapse capacity of buildings modelled by ASCE/SEI 41-13 are more than empirical method and fewer cases can pass the level of safety probability of failure suggested by ASCE/SEI-41.

Keywords

• shear and axial failures
• local and global collapse
• non-ductile reinforced concrete buildings
• fragility curves