A Simple and Effective Rigid Beam Model for Studying the Dynamic Behaviour of Freestanding Columns

== Abstract ==

In this work, a simple and effective Rigid Beam Model is proposed for studying the 
dynamic  behaviour  of  ancient  freestanding  stone  columns.  As  well  known,  monolithic  and 
multi-drum freestanding columns are historical structural elements typical of ancient temples 
that  still  can  be  found  in  the  Mediterranean  area.  These  columns  are  particularly  prone  to
collapse in case of seismic actions. The dynamic behaviour of freestanding columns has been 
studied by many authors in the past [1-3], and it is characterized by a strong nonlinearity due 
to sliding and rocking between the drums. The Rigid Beam Model here described assumes each 
drum of the column as a rigid beam element and each interface between the drums as a node 
of the model able to move horizontally. Similar to Housner [1] approach, this model assumes 
small displacements and no sliding between blocks. Furthermore, the material nonlinearity is 
considered by means of a moment-rotation constitutive law slightly modified with respect to the 
bilinear one introduced by Housner. Numerical simulations were performed on monolithic and 
multi-drum  columns  modelled  using  the  proposed  Rigid  Beam  Model  approach.  Results  are
compared  against  simulations  of  the  same  columns  undertaken  by  means  of  the  Discrete 
Element Model, which is able to consider large displacements and the possible sliding between 
the drums, and it has already proven its effectiveness in simulating column behaviour [2-4].

== Full document ==
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== References ==

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[5]  Baraldi,  D.,  Milani,  G.  and  Sarhosis,  V.  Numerical  models  for  simulating  the  dynamic behaviour of freestanding ancient columns. Compdyn 2019 Proceedings (2019), pp. 1526-1536.  

[6]  Cundall,  P.A.,  A  computer  model  for  simulating  progressive  large  scale  movements  in blocky rock systems. Proceedings of the Symposium of the International Society of Rock  Mechanics (1971), Nancy, France.  

[7]  Spanos,  P.D.  and  Koh,  A.-S.  Rocking  of  rigid  blocks  due  to  harmonic  shaking.  J.  Eng. Mech. (1984) 110(11):1627-1642.  

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