Fast Seismic Vulnerability Evaluation of Historical Masonry Aggregates through Local Analyses: an Adaptive NURBS-based Limit Analysis Approach

== Abstract ==

An efficient computational tool for the local failures analysis in historical masonry 
aggregates is proposed. A NURBS (Non-Uniform Rational B-Spline) representation of 
geometry is adopted. NURBS entities, which are common in commercial CAD packages, have 
the great advantage to describe complex geometries (such as curved elements and walls with a 
high number of holes) with very few elements. An upper bound limit analysis formulation is 
implemented, in which the adopted NURBS elements are idealized as rigid bodies with 
dissipation allowed only along interfaces. The mesh of NURBS elements is progressively 
adjusted through a genetic algorithm in order to minimize the live load multiplier. This 
procedure is applied in the evaluation of the horizontal load multiplier associated with the 
activation of local mechanisms during a seismic event. Some case studies, referring to masonry 
aggregates located in the historical centers of Arsita (Abruzzo region, Italy) and Sora (Lazio 
region, Italy), are here presented. A quick evaluation of the seismic vulnerability is performed 
through the presented NURBS-based computational tool, showing the high importance of the 
local response in the study of the seismic behavior of masonry aggregates.

== Full document ==
<pdf>Media:Draft_Content_466960571p649.pdf</pdf>
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