Effect of Structural Bonding Patterns on Mechanical Characteristics of Clay Brick Masonry under Different Loadings Using Digital Image Correlation Technique

Abstract

This paper assesses the effect of two different structural bonding patterns on the mechanical characteristics of clay brick masonry assemblages under compression, flexure, and shear loading conditions. A 2D digital image correlation technique (DIC) was used to appraise the nonlinear compressive stress-strain characteristics, orthotropic properties, damage, and failure mechanisms of masonry prisms. The experimental investigation ascertained that full-brick thick masonry exhibited reasonably higher capacity and deformation characteristics than half-brick thick masonry under compression, flexure, and diagonal compression loadings, except in bed joint shear strength. The compressive strength and corresponding strain of full-brick thick Flemish bond prisms were higher and had more deformable (maximum strain recorded 2.4 times) behavior than half-brick thick masonry prisms. The failure mechanics of the masonry was quantitatively established by strain analysis obtained from DIC. The rupture modulus of Flemish bond masonry walls was four times higher, and its failure (a combination of tensile splitting of bricks and bed joint failure) was gradual compared to stack bond masonry. The diagonal compression strength of full-brick thick masonry wallettes was about 1.3 times as large as running bond wallettes, as the bond arrangement resisted diagonal cracks propagation. The applicability of the available idealized compressive stress-strain analytical models was evaluated, and a few improvements were recommended. The research study assessed that due attention needs to be given to structural bonding patterns in evaluating the mechanical characteristics of masonry required in the design and analytical modelling of masonry constructions. DIC technique can be conveniently used to capture the nonlinear strain characteristics and can be handy in detecting the damage early.