Experimental Investigation on the Torsion-Shear Behaviour at the Interfaces of Interlocking Masonry Block Assemblages

== Abstract ==

This paper presents an experimental investigation on the initial shear (cohesion) 
and torsion-shear strengths at the interface of an interlocking masonry block. An interlocking 
block is a rigid unit with locks avoiding the block to slide. This improves the seismic response 
of  dry  jointed  assemblages  of  masonry  structures  subjected  to  in-plane  and  out-of-plane 
loading.  The  experimental  investigation  is  designed  and  carried  out  for  the  corrugated 
interface having one lock with rectangular cross section, i.e. the specimen is an interlocking 
unit composed of a main body and a lock located on the upper face of the main body. Cement-
based  mortars  are  selected  to  reproduce  the  specimen,  casted  using  a  mould  provided  by  a 
3D  printer,  and  both  the  lock  and  the  main  body  are  kept  rigid  during  the  tests.  The  initial 
shear and torsion-shear capacities of the interface at which the lock is connected to the main 
body  are  assessed  together  with  its  quasi-brittle  fracture  and  registered  in  terms  of  load-
displacement  curves.  In  the  designed  setup,  the  horizontal  force  is  applied  to  the  rigid  lock 
until it is disjointed from the rigid main body of the block, while the effect of rocking during 
the shear test is avoided. The force and the displacements are measured using a load cell and 
Linear Variable Displacement Transducers (LVDTs), respectively. The experimental 
programme  includes  four  different  sets  with  different  load  application  points  and  different 
load directions, each set repeated on a number of similar specimens. Empirical formulations 
between the initial shear and compressive strengths of the lock interface are also evaluated.

== Full document ==
<pdf>Media:Draft_Content_130603464p932.pdf</pdf>
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