Development and validation of simplified mechanics-based capacity curves for scenario-based risk assessment of school buildings in Basel. (15th April 2020)

• Record Type: Journal Article
• Authors: Hannewald, Pia; Michel, Clotaire; Lestuzzi, Pierino; Crowley, Helen; Pinguet, Justine; Fäh, Donat
• Is Part Of: Engineering structures. Volume 209(2020)
• Publication Date: 2020-04-15
• Subjects: Seismic vulnerability assessment -- Capacity curves -- Fragility curves -- Mechanical method -- Displacement-based evaluation; Structural engineering -- Periodicals; Structural analysis (Engineering) -- Periodicals; Construction, Technique de la -- Périodiques; Génie parasismique -- Périodiques; Pression du vent -- Périodiques; Earthquake engineering; Structural engineering; Wind-pressure; Periodicals; 624.105
• DOI: 10.1016/j.engstruct.2020.110290
• Languages: English
• ISSNs: 0141-0296

Abstract

Highlights: Nonlinear simplified mechanics-based models for the calculation of capacity curves were developed. Capacity curves were calculated for central European RC shear wall and URM building types. Typical construction details with their expected failure mechanisms were considered. Plausible results were obtained in earthquake scenarios based on these capacity curves. Abstract: This paper deals with the development of nonlinear static models for the calculation of capacity curves that are subsequently applied in a scenario-based assessment of school buildings. The investigated building types include unreinforced masonry buildings with rigid floors and reinforced concrete buildings with slender shear walls, both of which are typical in central Europe. The curves were established by means of simplified mechanics-based models of the structures together with the expected failure mechanisms of the structural members, from which bilinear capacity curves were calculated. These capacity curves were used to derive fragility curves for a number of predefined earthquake scenarios in Basel, Switzerland. This application revealed that with the initial capacity curves developed in this project, the damage in the earthquake scenarios was largely overestimated compared to that predicted from empirical intensity-based vulnerability models. The initial curves had been determined with models that made use of code recommendations for the assessment of existing structures together with experimental mean material characteristics. Modifications to the modelling procedure, including revised assumptions concerning the failure modes and changes to the assumed initial stiffness based on vibration measurements, led to revised curves which featured, in particular, increased ductility. With these updated and validated capacity curves, results closer to the empirical intensity-based models were obtained. While the type of modelling used herein has its limitations due to simplicity, it was still possible to account for the influence of typical characteristics (such as the detailing of RC walls) on the relative behaviour and response of the buildings, thus justifying the use of analytical capacity and fragility functions, as opposed to empirical intensity-based models, in the final risk assessment.