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Existing masonry buildings, representing a large portion of the building stock in the 

Mediterranean  area,  are  usually  characterized  by  the  presence  of  different  constituent 

materials.  The  modifications  experienced  over  time  could  have  modified  the  static 

configuration of the structures  and  could  trigger  local  damages  and  crises.  Therefore, 

it  is  of  fundamental importance  to  assess  the  safety  of  these  constructions  and  to 

determine  if  retrofitting interventions  are  needed.  In  this  framework,  one  of  the  crucial 

aspects  is  the  mechanical characterization of masonry. Concerning brick masonries, several 

testing  methodologies  exist  for the  determination  of the  compressive  strength,  the  elastic 

modulus  and  the  Poisson’s  ratio.  In  particular,  slightly-destructive  tests,  such  as  double 

flatjack  tests  and  compressive  tests  on  masonry  cores,  can  be  performed  in  place  of 

destructive  tests  due  to  their  limited  invasiveness.  However,  they  could  be  less 

representative  of  the  overall  behavior  of  masonry  structural elements. The objective of the 

research is to evaluate the reliability of slightly-destructive tests in evaluating the compressive 

properties of masonry. An experimental campaign is presented, in which masonry specimens 

were built to reproduce a poor-quality brick masonry typology. Standard compression tests 

on  wallets  and  double  flatjack  tests,  both  monotonic  and  cyclic,  were  performed. 

Moreover,  masonry  cores  were  extracted  from  the  masonry  specimens  and  tested  in 

compression.  Compressive  strength,  elastic  modulus  and  Poisson’s  ratio  were evaluated 

from each testing methodology. The results obtained from the double flatjack tests and the 

tests on cores, in terms of strength and deformability properties, were compared with the 

results  of  the  standard  compression  tests,  taken  as  reference.  Correlations  between  the 

results of the slightly-destructive tests and the standard compression tests were established, 

obtaining  a  good  agreement  and  confirming  that  the  experimental  techniques  can  be 

reliably adopted for the evaluation of the compressive properties of brick masonry.

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== Full document ==

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== References ==

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