Ricerc@Sapienza

The seismic design of fasteners used to anchor nonstructural components (NSCs) to concrete structures constitutes a crucial task within the context of a modern performance-based philosophy, which accounts for all the components of a building. This is particularly relevant when the NSCs are required to withstand strong seismic events with minor damage. The present paper introduces a new generation of high-performance post-installed anchors incorporating supplemental damping-referred to as EQ-Rod-for reducing the acceleration suffered by NSCs.

This research demonstrates the efficacy of 2–4 viscous dampers in self-centering rocking structures with bi‑linear elastic response, which is distinctly different to conventional fixed‑base structures. This study assesses the relative impact of 2–4 devices versus typical viscous dampers and 1–3 viscous devices. Performance is assessed by maximum displacement, total base shear, and maximum acceleration, which are indicative of structural, foundation and contents demand. Simultaneous reductions of displacement, base-shear and acceleration are only available with the 2–4 damper.

Since 2010, twelve post-tensioned timber (Pres-Lam) buildings have been constructed throughout the world. The technology relies on unbonded post-tensioning tendons to provide moment capacity to beam-column, wall-foundation, or column-foundation connections. Supplemental energy dissipation can be introduced by mild steel bars or replaceable damping devices when designing buildings for high seismic risk areas. Creep within the timber elements leads to losses in post-tensioning force over time.

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.

This paper presents the evaluation of the loss-of-support conditions in frictional beam-to-column connections of industrial precast concrete buildings under seismic actions. This type of connection is widespread throughout Southern Europe in non-seismically designed industrial precast buildings. First, geometric properties of industrial precast buildings and of the frictional beam-to-column connections, together with reference values for the friction coefficient, are reviewed.

It is well known that the incidence angle of seismic excitation has an influence on the structural response of buildings, and this effect can be more significant in the case of near-fault signals. However, current seismic codes do not include detailed requirements regarding the direction of application of the seismic action and they have only recently introduced specific provisions about near-fault earthquakes. Thus, engineers have the task of evaluating all the relevant directions or the most critical conditions case by case, in order to avoid underestimating structural demand.

The energy efficiency is the possibility and ability to carry out a production process consume with the involves of less energy and minor environmental impact. Life Cycle Assessment is one of the major tools involved in the economic, social and environmental evaluation. The aim of this work is the LCA application to an Italian company that provides to install a photovoltaic plant for the energy self-maintenance, in order to break down costs and environmental impacts. The photovoltaic business can be an interesting solution especially for companies which consume more energy during the day.

This paper describes the simulation of RC members with a three-dimensional (3D), 2-node beam finite element (FE) that includes warping of the cross section. A previously proposed FE formulation is extended to allow the description of structural members with softening material behavior. The governing equations are derived from an extended four-field Hu-Washizu variational principle, with independent interpolation of the warping displacement field from the rigid section displacement, the generalized section deformation, and the material stress fields.

Between August and November 2016, three major earthquake events occurred in Central Italy. The first event, with M6.1, took place on 24 August 2016, the second (M5.9) on 26 October, and the third (M6.5) on 30 October 2016. Each event was followed by numerous aftershocks. The 24 August event caused massive damages especially to the villages of Arquata del Tronto, Accumoli, Amatrice, and Pescara del Tronto. In total, there were 299 fatalities, generally from collapses of unreinforced masonry dwellings.

A graphical dynamic model is presented to predict the directional earthquake response of two-ways plan-asymmetric buildings. The theoretical principles inherent to torsional dynamics and vibrations are investigated and the dynamic directional response is rationally explained based on modal rotational kinematics about modal torsional pivots.