A comparative study on a complex URM building: part II—issues on modelling and seismic analysis through continuum and discrete-macroelement models

Abstract

The paper presents the comparison of the results obtained on a masonry building by nonlinear static analysis using different software operating in the field of continuum and discrete-macroelement modeling. The structure is inspired by an actual building, the "P. Capuzi" school in Visso (Macerata, Italy), seriously damaged following the seismic events that affected Central Italy from August 2016 to January 2017. The activity described is part of a wider research program carried out by various units involved in the ReLUIS 2017/2108—Masonry Structures project and having as its object the analysis of benchmark structures for the evaluation of the reliability of software packages. The comparison of analysis was carried out in relation to: global parameters (concerning the dynamic properties, capacity curves and, equivalent bilinear curves), synthetic parameters of structural safety (such as, for example, the maximum acceleration compatible with the life safety limit state) and the response in terms of simulated damage. The results allow for some insights on the use of continuum and discrete-macroelement modeling, with respect to the dispersion of the results and on the potential repercussions in the professional field. This response was also analyzed considering different approaches for the application of loads.

Modelling the nonlinear static response of a 2-storey URM benchmark case study: comparison among different modelling strategies using two- and three-dimensional elements

“…The two FE models agree in terms of smoothed loss of resistance In the same graph a grey band, corresponding to the envelope of the results obtained in Manzini et al (2020) with EF models for the same configuration of the building, is reported; although the peak resistance scatter embeds the corresponding values obtained with software A and B, a major discrepancy with respect to the models employed in the present study is encountered in terms of initial stiffness. It is worth noting that the initial stiffness, as also explained in Castellazzi et al (2021), are set according to a conventional degradation in the case of EF models (assuming a coefficient of reduction of the elastic stiffness equal to 0.5), and considering a progressive degradation associated to the evolution of damage for all the models adopted in this study. Therefore, the difference in terms of initial stiffness can be justified with the different assumptions in terms of elastic mechanical properties and are consistent with the results obtained at the real building scale in Castellazzi et al (2021).…”

“…It is worth noting that the initial stiffness, as also explained in Castellazzi et al (2021), are set according to a conventional degradation in the case of EF models (assuming a coefficient of reduction of the elastic stiffness equal to 0.5), and considering a progressive degradation associated to the evolution of damage for all the models adopted in this study. Therefore, the difference in terms of initial stiffness can be justified with the different assumptions in terms of elastic mechanical properties and are consistent with the results obtained at the real building scale in Castellazzi et al (2021). In addition, the EF models show a higher scatter in terms of initial stiffness with respect to the models here employed, for which the discrepancy is basically negligible.…”

“…The studied benchmark structures range from single panels (D'Altri et al 2021), studied for different boundary conditions, axial load and aspect ratios, to real 3D buildings, such as a school located in Visso (Italy) heavily damaged by the seismic sequence that struck the central Italy in 2016 (Ottonelli et al 2021;Castellazzi et al 2021), that is modelled and investigated. A summary of the goals of this coordinated research can be found in Cattari and Magenes (2021), which also describes all the analysed benchmark structures, studied by means of different software packages.…”

Preface to special issue on numerical modelling of URM buildings: benchmark project

“…The following three papers are based on 3D complex configurations, inspired by real existing buildings. Ottonelli et al (2021) and Castellazzi et al (2021) analyse a benchmark building based on the P. Capuzi school in Visso, while Degli Abbati et al ( 2021) examines a building inspired by the Pizzoli town hall. These buildings are very interesting being permanently monitored by the Italian Department of Civil Protection and having been hit by the Central Italy 2016-2017 earthquake.…”

“…Finally, in Occhipinti et al (2021) the comparative study on a 2D multi storey wall is illustrated by focusing on the use of finite and discrete element models.…”