Modified masonry triplets for the shear characterisation and numerical modelling of NFRCM-strengthened masonry

The evaluation of shear performance of masonry strengthened with Natural Fiber Reinforced Cementitious Matrix (NFRCM), adopting “modified” triplet specimens, derived from the Representative Elementary Volume (REV) of the running bond masonry texture, is presented in this research. Diagonal Compression Tests (DCT) were conducted, and an adapted Digital Image Correlation (DIC) technique was adopted to capture the deformation at the microstructural level. Two specimen configurations were studied: an unreinforced triplet and a triplet strengthened with bidirectional jute mesh-reinforced NFRCM. The results demonstrate an improvement in the shear resistance and deformation capacity in the strengthened specimens. Further, a Finite Element (FE) model based on a multi-leaf homogenization technique was also adopted and was validated based on the experimental outcomes. With this, the research presented, aims at combining novel small-scale specimen derived from a REV where the microstructure is significant, with the well-established shear identification with DCT, to demonstrate an accessible and sustainable testing methodology for masonry, advancing the understanding of micromechanical interactions in strengthened masonry.