Second release of the CoRe database of binary neutron star merger waveforms

We present the second data release of gravitational waveforms from binaryneutron star merger simulations performed by the Computational Relativity(CoRe) collaboration. The current database consists of 254 different binaryneutron star configurations and a total of 590 individual numerical-relativitysimulations using various grid resolutions. The released waveform data containthe strain and the Weyl curvature multipoles up to $\ell=m=4$. They span asignificant portion of the mass, mass-ratio,spin and eccentricity parameterspace and include targeted configurations to the events GW170817 and GW190425.CoRe simulations are performed with 18 different equations of state, seven ofwhich are finite temperature models, and three of which account fornon-hadronic degrees of freedom. About half of the released data are computedwith high-order hydrodynamics schemes for tens of orbits to merger; the otherhalf is computed with advanced microphysics. We showcase a standard waveformerror analysis and discuss the accuracy of the database in terms offaithfulness. We present ready-to-use fitting formulas for equation ofstate-insensitive relations at merger (e.g. merger frequency), luminosity peak,and post-merger spectrum.<br

New national and regional Annex I Habitat records: from #60 to #82

New Italian data on the distribution of the Annex I Habitats are reported in this contribution. Specifically, 8 new occurrences in Natura 2000 sites are presented and 49 new cells are added in the EEA 10 km × 10 km reference grid. The new data refer to the Italian administrative regions of Campania, Calabria, Marche, Piedmont, Sardinia, Sicily, Tuscany and Umbria. Relevés and figures are provided as Supplementary material respectively 1 and 2. Copyright Antonio Morabito et al

On the use of continuum Finite Element and Equivalent Frame models for the seismic assessment of masonry walls

The assessment of the seismic vulnerability of masonry buildings requires reliable and computationally efficient numerical models. Different modelling strategies can be adopted when studying the global response of these structures, such as Continuum Constitutive Laws Models (CCLM) belonging to Finite Element (FE) models, which may be very accurate but whose use in practice presents several issues (high computational burden, requirement of many input data), and Equivalent Frame (EF) Models, that, even if based on strong simplifications, are now widespread in engineering practice, thanks to their computational efficiency and the need of few mechanical parameters for the structural analysis. The paper discusses the consistent use of these modelling techniques for the seismic analysis of masonry structures. To this aim, a comparison of two approaches (CCL and EF models) is presented focusing at first the attention on the calibration of the constitutive laws through analyses on single panels and then moving to the validation of some simplified assumptions made in the EFM through the analysis of a 2D regular URM wall. For the aim of validation, the CCL model is considered as the reference solution making an accurate comparison with the EF model in terms of generalized forces, drift and damage occurred at element scale and of pushover curve at global scale

RINTC project: Nonlinear dynamic analyses of Italian code-conforming URM buildings for collapse risk assessment

This paper deals with the computation of the collapse risk of new masonry buildings designed according to the Italian Building Code. Companion papers describe the overall EUCENTRE-ReLUIS joint research project, funded by the Italian Department of Civil Protection (DPC), which considers different building types (r.c., steel buildings, etc) and uses multi-stripe nonlinear dynamic analyses by properly selected ground motion records. 2- and 3-storey unreinforced masonry buildings have been designed in cities with increasing seismic hazard, considering two different soil conditions at each site. First, the paper describes geometry, material characteristics (clay block masonry) and main structural details of the buildings, discussing the effect of different design methods (rules for simple buildings, linear and nonlinear static analysis) and models (cantilever or equivalent-frame models). The models used for the assessment by nonlinear dynamic analyses are equivalent-frame models made by masonry piers and spandrels, as well as reinforced concrete members. Two alternative macroelement models are used for the in-plane response of masonry members. Out-of-plane failure modes are assumed to be prevented by the presence of ring beams and limited slenderness of masonry walls. Pushover analyses are used to esti-mate the EDP (maximum inter-storey drift ratio) threshold for the collapse limit state. Finally, the results of the multi-stripe analyses are presented for 10 different earthquake's return periods

Storia e problemi contemporanei

Rivista quadrimestrale che affronta temi e questioni di storia contemporanea. Ogni numero \ue8 monografico

Storia e problemi contemporanei

Rivista quadrimestrale che affronta temi e questioni di storia contemporanea. Ogni numero \ue8 monografico