Applicability of FEM and Pushover Analysis to Simulate the Shaking-Table Response of a Masonry Building Model with Timber Diaphragms

== Abstract ==

The  seismic  behaviour  of  unreinforced  masonry  (URM)  structures  is  generally 
governed  by  a  complex  interaction  between  the  out-of-plane  and  in-plane  responses  of  the 
walls, depending on the in-plane stiffness of floor/roof diaphragms and the efficiency of wall-
to-floor/roof connections. The presence of timber diaphragms, which are typically characterised  by  low  in-plane  stiffness  and  poor  connection  to  the  masonry  walls,  adds challenges to the numerical modelling and analysis, as well as to the structural assessment of URM  structures  under  seismic  actions.  This  work  aims  at  investigating  the  applicability  of refined  FE modelling  using  macro-modelling  approach  and  mass-proportional  pushover analysis for simulating the response of URM structures with flexible diaphragms, comparing the results with experimental data obtained from incremental dynamic testing. 
A  full-scale  two-storey  prototype  building  with  timber  diaphragms,  which  was  tested  in 
shaking table at the European Centre for Training and Research in Earthquake Engineering 
(EUCENTRE),  in  Italy,  was  considered  to  perform  this  study.  A  refined  finite  element  (FE)
model was developed in DIANA software, considering the wall-to-diaphragm (WTD) 
connections.  While  the  strength  values  of  masonry  were  adopted  according  to  axial  and 
diagonal compression tests, the modulus of elasticity was calibrated after simulating in-plane 
cyclic  shear  tests  of  masonry  piers,  which  were  part  of  the  same  experimental  program  at EUCENTRE. Recommendations from international guidelines were used to derive the assumed 
material  properties  for  diaphragms  and  wall-to-diaphragm  connections.  Mass-proportional 
pushover  analysis  was  performed  and  a  comparison  between  numerical  and  experimental 
results is presented to investigate the assumptions, advantages and limitations of the presented 
numerical modelling and analysis approach.

== Full document ==
<pdf>Media:Draft_Content_751443795p1164.pdf</pdf>
== References ==

[1] Lourenço,  P.B.,  Mendes,  N.,  Ramos,  L.F.  and  Oliveira,  D.V.  Analysis  of  masonry  structures without box behavior. Int J Archit Herit (2011) 5:369-382.  https://doi.org/10.1080/15583058.2010.528824.  

[2] NTC 2018. Norme Tecniche per le Costruzioni. Decreto Ministeriale 17/1/2018 (2018).  

[3] NZSEE  2017.  The  existing  Assessment  of  Existing  Buildings.  Part  C8:  Unreinforced Masonry Buildings (2017).  

[4] ASCE/SEI 41-13. Seismic Evaluation and Retrofit of Existing Buildings (2014).  

[5] Brignola, A., Pampanin, S., Podestà, S. Evaluation and control of the in-plane stiffness of  timber  floors  for  the  performance-based  retrofit  of  URM  buildings.  Bull  New  Zeal  Soc  Earthq Eng (2009). https://doi.org/10.5459/bnzsee.42.3.204-221.  

[6] Magenes,  G.,  Penna,  A.,  Senaldi,  I.,  Galasco,  A.  Shaking  Table  Test  of  a  Strengthened  Full-Scale  Stone  Masonry Building with  Flexible Diaphragms.  Int J Archit Herit (2014)  8:349–375. https://doi.org/10.1080/15583058.2013.826299.  

[7] Senaldi, I., Magenes, G., Penna, A., Galasco, A., Rota, M. The Effect of Stiffened Floor  and Roof Diaphragms on the Experimental Seismic Response of a Full-Scale Unreinforced  Stone Masonry Building. J Earthq Eng (2014) 18:407–43.  https://doi.org/10.1080/13632469.2013.876946.  

[8] Magenes, G., Penna, A., Galasco, A. A full-scale shaking table test on a two-storey stone  masonry building. In: Proceedings of the 14th European Conference Earthquake  Engineering (2010).  

[9] Senaldi, I. The influence of floor and roof diaphragms on the seismic response of existing  masonry buildings. PhD Thesis, School of Advanced Studies IUSS Pavia, Italy (2012).  

[10] Magenes, G., Penna, A., Galasco, A., Da Paré, M. In-plane cyclic shear tests of undressed double-leaf  stone  masonry  panels.  In:  Proceedings  of  the  8th  International  Masonry Conference (2010).   

[11] DIANA  FEA  BV.  Diana  User’s  Manual,  Release  10.3.  DIANA  FEA  BV  2019.  https://doi.org/10.1080/15421400600788682.  

[12] Magenes,  G.,  Penna,  A.,  Galasco,  A.,  Rota,  M.  Experimental  characterisation  of  stone masonry mechanical properties. In: Proceedings of the 8th International Masonry  Conference (2010). 

[13] EN 338:2016. Structural timber - Strength classes. European Committee for  Standardization, Brussels, Belgium.  

[14] Kouris, L.A.S., Penna, A., Magenes, G. Dynamic Modification and Damage Propagation  of a Two-Storey Full-Scale Masonry Building. Adv. Civ. Eng (2019).  https://doi.org/10.1155/2019/2396452.  

[15] Schreppers, G.M., Garofalo, A., Messali, F., Rots, J. DIANA Validation report for Masonry modelling (2017).  

[16] Vaculik,  J..  Unreinforced  masonry  walls  subjected  to  out-of-plane  seismic  actions.  PhD Thesis, University of Adelaide, Australia (2012).