Publications

La presente Prova Finale si pone l’obiettivo di studiare e analizzare la situazione attuale (maggio 2017) del Servizio Sanitario Regionale Veneto, di comprendere e spiegare il concetto di Integrazione e di compiere un particolare focus in merito alla domanda e all’offerta sanitaria nella nuova Azienda Ulss 1 Dolomiti.

The aim of this paper is to identify the relations between cities and citizens regarding sustainability. We identify clusters of European regions on Sustainable Development Goals based on statistical indicators. We collect and treat data on the ranking of Europeans on Sustainable Development Goals obtained from on-line questionnaires done in different regions in Europe. Using Principal Component Analysist on the composed responses we name them based on the identification of their parts and related their extracted values with the features of the respondents. We conclude not only that the place of the respondents shows significative coefficients in explaining the various components but also that the attitudes implicit in each component favours the goals that are not achieved in the place “People and Places chose what they do not have”.

Until recently, the viscous damping ratio pervasively assumed has been ζ=5%. However, the dynamic identification of the experimental response recorded in recent large-scale shake-table tests shows that lower levels of viscous damping are more appropriate when material nonlinearities are explicitly accounted for. This paper investigates a hybrid constant-ductility inelastic displacement ratio, Cμ2, which identifies the inelastic demand for a viscous damping ratio ζ=2% when the elastic demand for ζ=5% is known. A comprehensive statistical analysis is developed, and analytical estimates are provided, for inelastic single-degree-of-freedom systems with a wide variation of the constitutive parameters and a large earthquake database.

Issues with traditional implementations of tangent-stiffness-proportional damping model are associated with negative damping forces that develop in the post-yield range when the system stiffness becomes negative and with unrealistic damping forces arising at degrees of freedom undergoing second-order movements only. To overcome these issues, this paper proposes a localized formulation of the tangent-stiffness-proportional damping model which can be used in nonlinear dynamic analysis of simple inelastic systems. Results show the consistency of the local and global damping formulations in small displacements and the effectiveness of the localized tangent-stiffness-proportional damping model in the presence of material and geometrical nonlinearities.

La presente Prova Finale si pone l’obiettivo di studiare e analizzare la situazione attuale (maggio 2017) del Servizio Sanitario Regionale Veneto, di comprendere e spiegare il concetto di Integrazione e di compiere un particolare focus in merito alla domanda e all’offerta sanitaria nella nuova Azienda Ulss 1 Dolomiti.

Summary This paper focuses on constant‐ductility inelastic displacement ratios of self‐centering single‐degree‐of‐freedom (SDF) systems with two different levels of energy dissipation capacity, in the presence of 5% viscous damping ratio. A statistical analysis is developed considering an earthquake database composed of 228 ground motions recorded in California with magnitudes greater than six and organized for NEHRP soil class, ground motion duration, and peak ground acceleration. The response of self‐centering SDF systems with large variability of initial periods, ductility levels, and postyield stiffness ratios is investigated and compared with the responses of SDF systems with bilinear plastic, Clough, and Takeda hysteresis. The inelastic demand variation with soil class, initial period, postyield stiffness ratio, unloading stiffness degradation, ductility level, and hysteretic behavior is highlighted. Simple and conservative analytical estimates of constant‐ductility inelastic displacement ratios for mean and 90th percentile values in terms of initial period, ductility level, and postyield stiffness ratio are proposed to allow the extension of the Displacement‐Based Design via Inelastic Displacement Ratio ( C μ DBD) to self‐centering structural systems.

Abstract Studies in the literature have shown that P‐delta () effects are highly influenced by the hysteretic characteristics of a structural system. However, international buildings and bridge codes prescribe ‐induced amplification factors, limits for negligible effects and limits for dynamic instability that neglect this influence. As a result, different margins of safety against actions are currently specified for different structural systems, with steel structures, for example, presenting reduced margins of safety with respect to concrete structures. Adopting a sub‐set of the PEER earthquake record database composed of 1964 earthquake records, this paper presents a statistical analysis of displacement amplification ratios for systems with different hysteretic models, fundamental periods and ductility levels. In terms of both elastic and inelastic stability coefficients, limit values of the stability coefficient for negligible effects and dynamic instability are proposed for the most common structural typologies, such as steel, well and poorly detailed reinforced concrete, and self‐centering structures. Analytical estimates of the median, 84th and 98th percentile values of the displacement amplification that take into account the combined effect of stability coefficient, ductility level and hysteretic properties are proposed.

P-delta ( PΔ) effects can worsen the seismic performance of building and bridge structures and potentially lead to dynamic instability and collapse. An accurate characterization of PΔ effects is therefore imperative, for both design and assessment of structures. Adopting an earthquake database composed of 7032 ground motions, this article uses the results of a large statistical analysis of amplifications of the displacement demand due to PΔ effects for bilinear single-degree-of-freedom systems to investigate and improve practice-oriented methods to account for PΔ effects. A large range of fundamental periods, ductility levels, and effective heights are investigated, and limits for dynamic instability and negligible PΔ effects are examined in terms of both elastic and inelastic stability coefficients. It is seen that systems with the same stability coefficient present increased PΔ induced displacement amplification with reducing fundamental period and increasing ductility level. New expressions for estimation of the median values of the PΔ displacement amplification ratio are proposed that take into account the combined effect of stability coefficient, ductility level, and fundamental period with improved transition close to dynamic instability. Results of the numerical analyses indicate that the new expressions provide improved accuracy over existing approaches without undue complexity.