Seismic risk evaluation of existing masonry buildings: methods and uncertainties

Abstract

<p>Masonry structures represent a large part of existing buildings. As confirmed by the damage caused by recent seismic events, the assessment of seismic performance of existing masonry building is then a critical issue in Countries exposed to seismic risk. Moreover, common methods of analysis based on non-linear static approach are significantly influenced by the assumptions about the shear behavior of masonry walls and may lead to inconsistent or contradictory results.</p><p>Due to the relevance of the problem ad hoc studies have been performed to clarify how the most relevant parameters affect the theoretical structural behavior and to setup a proper method to define these parameters.</p><p>In the paper, the main sources of uncertainties regarding the definition of material parameters are investigated and a methodology for the identification of masonry classes is illustrated discussing the propagation of uncertainties related to masonry parameters in non-linear static analysis of masonry buildings. The analysis are carried out through a simplified non-linear pushover type algorithm developed by the authors and the outcomes are illustrated and critically discussed for a relevant case study.</p><p>The results show the capability of the proposed procedure for the identification of masonry classes and the evaluation of masonry mechanical parameters to provide a more refined probabilistic assessment of the seismic risk index.</p>

Experimental Evaluation of Shear Behavior of Stone Masonry Wall

“…The bilinear approximation represents the so-called capacity curve, which is generally adopted to model the nonlinear behavior of masonry walls in seismic analysis [ 27 , 28 , 29 , 30 ]. Masonry panels are modelled as Timoshenko’s beams characterized by the stiffness where is the height of the panel, is the shear span, is the area of the gross section, is the moment of inertia of the gross section, and and are the elastic and shear modulus, respectively.…”

“…Let be V max the maximum shear force measured during the test, the effective stiffness k e f is given by the secant stiffness at 0.7 V max , while the ultimate displacement δ ult is defined as the value corresponding to a significant drop ∆V of the descending part of the experimental V − δ curve, for example, ∆V = 0.2 V max , or as the largest drift reached during the test, if such a large drop ∆V is not attained [16]. The bilinear approximation represents the so-called capacity curve, which is generally adopted to model the nonlinear behavior of masonry walls in seismic analysis [27][28][29][30]. Masonry panels are modelled as Timoshenko's beams characterized by the stiffness…”

Non-linear Methods for the Assessment of Seismic Vulnerability of Masonry Historical Buildings

“…In the discussion particular attention is devoted to the different material constitutive laws adopted in each software program (Croce et al 2019b).…”

Influence of the Elasto-Plastic Behavior of Tie-Rods in the Response of Rocking Masonry Walls Through Seismic Demand Hazard Curves

“…Moreover, this paper adopts a full stochastic approach for the seismic vulnerability assessment [23]- [26], whereas in [22] a semi-probabilistic approach is considered. After the presentation of the analytical formulation (Section 2) and the assumptions (Section 3) taken into account in the analysis, the work discusses the results in terms of fragility curves (Section 4) and seismic hazard curves (Section 5), which is a new frontier in the probabilistic assessment of seismic vulnerability [27].…”