An Integrated Modeling Approach that Combines Elastic Amplification and Rocking Analysis for Seismic Assessment of a Masonry Tower

== Abstract ==

Failure  of  masonry  structures  during  earthquakes  often  occurs  via  specific,  well-
documented collapse mechanisms, many of which involve partial collapse of the structure well 
above ground level. Consequently, the elastic response of the structure needs to be considered, 
which in the case of historic structures such as bell towers and churches often requires modal 
analysis using finite element models - the generation of which can be labour-intensive and time-
consuming.  This  paper  presents  a  new  integrated  modeling  approach  which  combines  finite
element  analysis  with  rocking  dynamics  in  order  to  model  the  seismic  response  of  complex structural geometries in a computationally-efficient manner. The modeling strategy is 
implemented  within  COMPAS  -  an  open-source  computational  framework  that  provides 
geometry  processing  independent  of  CAD  software,  and  is  incorporated  within  the  broader 
framework of a tool being developed for the seismic collapse assessment of masonry structures. 
The framework of this new tool is first outlined, and the utility of the new modeling approach 
then demonstrated through application to the seismic assessment of a historic masonry tower 
in North-Eastern Italy. The analysis results indicate that for the level of seismic hazard expected 
on site, failure of the tower is most likely to occur via overturning collapse of one of the rampart 
elements. The importance of accounting for elastic amplification effects, as well as the influence 
of varying boundary conditions on the dynamic response, is also demonstrated.

== Full document ==
<pdf>Media:Draft_Content_483500617p708.pdf</pdf>
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