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Innovative damage-mitigation technologies have been recently developed to improve the seismic performance of structural and non-structural elements. The combination of these solutions can lead to a high-performance and cost-efficient building system, capable of sustaining earthquakes with limited damage and reduced socio-economic losses. This article investigates the convenience of implementing damage-control solutions through a cost/performance-based evaluation of multi-story-reinforced concrete buildings, comprising alternative combinations of traditional vs low-damage technologies for both structural skeletons (frames, walls) and non-structural elements (heavy/light facades, heavy/light partitions, suspended ceilings). The significant benefits of the innovative systems are investigated through loss assessment studies, implemented using a practical approach based on numerical pushover analyses and the capacity spectrum method. The parametric analyses confirm that the integrated low-damage structural/non-structural system can lead to significant savings, in these specific cases, in the range of 150–300 €/m2 during the 50-year building-life and downtime reductions at ultimate limit state in the order of 2–7 months.

Recent earthquakes highlighted the structural deficiencies of non-ductile reinforced concrete buildings that are characterized by the absence of any seismic design criteria and by the significant vulnerability of the joint region. Yet, a common engineering practice consists in modeling the beam-column joints as rigid elements in concrete frames. Furthermore, when considering a rigid joint model, the local and global collapse mechanisms of the structure can change significantly from the actual one, given the key role represented by joint's deformability and its actual capacity in a more accurate modeling approach. In the past two decades comprehensive experimental and numerical investigations have been carried out to better understand the role and behavior of substandard beam-column joints and propose simple while reliable modeling approaches depending on the structural detailing and consistent with the needs of a daily use in engineering practice. This paper provides a short overview of typical and more recent approaches adopted to capture the behavior of older RC beam-column joint subsystems. The goal is to highlight some open issues concerning the numerical models and experimental testing, also analyzing the performance and the critical issues of literature's results.

On the basis of recent developments in post-tensioned multi-storey timber buildings using un bonded tendons, this paper aimed at investigating the potential of implementing a similar techno...

The new guidelines for the seismic assessment of existing buildings recently introduced by the New Zealand Society for Earthquake Engineering (NZSEE) recommend the Simple Lateral Mechanism Analysis (SLaMA) as an “analytical” first phase of any other numerically-based analysis. This article illustrates the development of the SLaMA method and its validation with reference to an existing RC building severely damaged during the Christchurch earthquake (2011). The capacity of the lateral resisting systems is assessed from component/subassembly to system level. The comparison of the results with observed damage and with the outcomes of refined numerical analyses confirms the effectiveness of this method

Recent seismic events are a unique opportunity to monitor and collect details of direct repair costs and the downtimes associated with massive reconstruction processes. This paper focuses on the actual repair costs of five RC buildings damaged by the 2009 L'Aquila earthquake. The repair costs for structural and nonstructural components that experienced different types of earthquake damage are discussed and then used as a benchmark for the predictions. The comparison at both the building and component levels revealed that the FEMA P-58 methodology is suitable, in general, for application to different types of building stock. Ad hoc upgrades to the FEMA fragility database for components that are typical of the Mediterranean area are required. When implementing the proposed modifications, a reasonable level of consistency is achieved in terms of actual and predicted repair costs (differences in the range of 30–48%). A discussion on the actual repair costs and the main differences with the predicted costs for infills and partitions, structural subassemblies, floor finishes, and other acceleration-sensitive nonstructural components is provided, along with suggestions for further improving.

How can we evaluate the cost-effectiveness of retrofit interventions aiming at reducing the seismic vulnerability of an existing building? What level of shaking intensity should the retrofitted building sustain? These are open questions affecting either the pre-earthquake prevention, the post-earthquake emergency and the reconstruction phases. The (mis)conception that the cost of retrofit interventions would increase linearly with the level of safety required in designing the intervention often discourages stakeholders to consider alternative retrofit options. As a result, a minimum (in some cases prescribed by-law) level of safety is often targeted, leading in some cases to no-action. Furthermore, the performance measure enforcing owners to take action is generally evaluated following a deterministic approach. When the assessment does not directly reflect, even in simplified terms, epistemic uncertainties and aleatory randomness, it can result in misleading confidence on the expected performance. The present study aims at contributing to the delicate decision-making process of retrofitting existing structures, by developing a framework to assist stakeholders with the evaluation of the actual improvement of the performance, expressed in terms of reduction of collapse probability, of alternative strategies of intervention as well as targeted retrofit levels. With reference to a pre-1970 case study building located in New Zealand, alternative retrofit solutions are considered, targeting different levels of performance, and the probability of reaching collapse when considering a set of ground-motions is evaluated, providing a correlation between the deterministic safety index adopted in the design phase (named "Percentage of New Building Standard" adopting New Zealand regulations) and the expected annual probability of collapse.

Seismic events are a major factor to consider in structural design of buildings in many countries. With the purpose of saving lives, most of the design codes lead to structural solutions that withstand large seismic actions without collapsing, but without taking into account a possible usage of the structures after the earthquake. As a result, it is necessary to consider the time needed to repair/retrofit the damaged structures (i.e. the downtime) since this period of inactivity may result in huge financial implications for the occupants of the buildings. In order to minimise the damages and simplify repair operations, structural solutions with rocking systems and negligible residual displacements have been developed during the last two decades. Systems with precast concrete rocking walls were studied with the aim of investigat- ing suitable and convenient structural alternatives to minimise the damage in case of an earthquake. Experimental, numerical and analytical analyses on post-tensioned solutions, with and without energy dissipation devices, were carried out in this research. The energy dissipation devices were made from steel angles that were further developed during the research. Different solutions for these devices were experimentally tested under cyclic loading and the results are presented. Numerical and analytical work on steel angles was also carried out. Regarding the concrete rocking wall systems, two concrete rocking wall systems were studied: post-tensioned walls and post-tensioned walls with energy dissipation devices. In the latter, the solution was to fix them externally to the wall, allowing their easy replacement after an earthquake. It is shown that the dissipaters are a viable solution for use in precast concrete rocking wall systems. A building case study is presented. The comparison between a traditional monolithic system and a hybrid solution was carried out, allowing the evaluation of the efficiency of the solution that was developed. Fundação para a Ciência e a Tecnologia - Project PRECA-SEISMIC (PTDC/ECM/116161/2009) and a PhD scholarship (SFRH/BD/46114/2008)

PELL, Public Energy Living Lab, is a platform conceived to support the Public Administration in Italy towards the definition and implementation of interventions on public buildings, aiming to jointly pursue their seismic safety, energy efficiency and environmental certification. This paper presents the on-going activities for the development of the platform PELL-Schools, focusing, in particular, on the “Seismic-Response” module that aims to become a standardized and interoperable database for the collection and collation of relevant data for the seismic vulnerability assessment and for the seismic monitoring of Italian schools. In order to test, tune and modify, if necessary, the proposed PELL-School Seismic-Response module and to contribute to its implementation on Italian school buildings a Working Group has been set up involving several Italian municipalities and stakeholders. The paper concludes with a call to action in viting researchers working on the seismic vulnerability assessment and monitoring of strategic buildings to join the Working Group to contribute their knowledge towards the commo n goal of guarantying the seismic safety of schools and other strategic buildings in Italy