Stick model for as-built and retrofitted infilled RC frames. (1st October 2022)

• Record Type: Journal Article
• Authors: Gaetani d'Aragona, M.; Polese, M.; Prota, A.
• Is Part Of: Engineering structures. Volume 268(2022)
• Publication Date: 2022-10-01
• Subjects: Infilled frame -- Shear-type behavior -- Engineering demand parameters -- Brittle failure -- Brittle collapse modes; 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.2022.114735
• Languages: English
• ISSNs: 0141-0296

Abstract

Highlights: Stick: Multi-Degree of Freedom shear model for Nonlinear Response History Analysis. Stick model generated for infilled RC frames in as-built and retrofitted configuration. Generation of interstory backbone curves via a simplified procedure. Applicability of Stick model for speed performance assessment at the community-scale. Abstract: The Stick model is a MDOF system composed of masses lumped at the story level, connected in series by nonlinear shear link elements suitably calibrated to simulate the interstory inelastic behavior. The model has been demonstrated to predict with sufficient accuracy the dynamic response of existing masonry-infilled RC structures in terms of damage concentration and evolution under specific ground motion records. Previous works proposed interstory backbones calibrated on the response of refined MDOF finite element models representative of gravity-load designed buildings. In this work, with the aim of extending the applicability of the Stick model to different building typologies, a simplified procedure is proposed to generate interstory backbones for the Stick model simulating the behavior of existing masonry-infilled RC structures in as-built and retrofitted configurations. The procedure allows generating Stick models accounting for different levels of design (gravity load, obsolete seismic codes), age of construction, number of storeys and in-plan shape and dimensions. Relevant features characterizing existing buildings are accounted for, explicitly simulating typical failure modes of non-conforming RC elements, brittle failures induced by local frame-infill interaction phenomena, and introducing typical building-level collapse modes for existing buildings. The proposed procedure is extended to account for the possible implementation of retrofit intervention at the building level to both increase the structural capacity and the stiffness of the building. The proposed procedure can be employed to generate typological Stick models to be adopted in large-scale loss assessment studies, also evidencing the beneficial effect of possible retrofit interventions.