Motion control-based seismic retrofit solutions for a R/C school building designed with earlier Technical Standards

Abstract

The study of two motion control-based seismic retrofit solutions for a low-rise reinforced concrete school building is presented in this paper. The building was assumed as a benchmark structure for a Research Project financed by the Italian Department of Civil Protection, and is representative of several similar public edifices designed with earlier Technical Standards editions, in Italy as well as in other earthquake-prone European countries. The two solutions refer to the alternative earthquake protection strategies based on the concepts of supplemental damping and seismic isolation, respectively. Namely, they consist in the installation of: (1) a dissipative bracing system incorporating pressurized fluid viscous spring-dampers; and (2) a base isolation system including double friction pendulum sliding bearings. The structural characteristics of the building, and a synthesis of the investigation campaigns developed on it, are initially presented. The mechanical parameters, dimensions, locations and installation details of the constituting elements of the two protective systems are then illustrated, along with the performance assessment analyses carried out in original and rehabilitated conditions according to a full non-linear dynamic approach. The results of the analyses show a remarkable enhancement of the seismic response capacities of the structure for both retrofit hypotheses. This allows reaching the mutual high performance levels postulated in the two rehabilitation designs with remarkably lower costs and architectural intrusion as compared to traditional rehabilitation interventions designed for the same objectives. © 2014, Springer Science+Business Media Dordrecht

Energy-Based Design Criterion of Dissipative Bracing Systems for the Seismic Retrofit of Frame Structures

“…This is owed to their high damping capacities, stable mechanical properties over time, simple installation procedures, limited architectural and visual impact, competitive costs and, in the case of pressurized elements, inherent self-centering qualities [54][55][56][57].…”

Life-Cycle Cost Model and Design Optimization of Base-Isolated Building Structures

“…In the case of HDNR systems, the natural rubber compound is used in order to have adequate inherent damping; while in the case of LRB systems, similar to low-damping rubber bearings, a central lead plug is used in order to increase the initial stiffness and energy dissipation capacity of the bearing. Many studies contributed to the evolution of base isolation during the last decades, in particular (Kelly, 1986(Kelly, , 1999Constantinou et al, 1990;Mokha et al, 1990;Skinner et al, 1992;Nagarajaiah et al, 1993;Naeim and Kelly, 1999;Symans and Constantinou, 1999;Providakis, 2008;Kilar and Koren, 2009;Morgan and Mahin, 2010;Pant et al, 2013;Sorace and Terenzi, 2014;Mazza and Mazza, 2016).…”

Application of a Direct Procedure for the Seismic Retrofit of a R/C School Building Equipped with Viscous Dampers

“…The structure was designed according to the building code in force in the 1970s in Italy for a medium risk seismic region, but prior modern seismic design methodologies. Additional details regarding the building structure can be found in the work by Mazza and Vulcano (2014) and Sorace and Terenzi (2014).…”