Micromechanical analysis of adobe masonry as two-component composite: Influence of bond and loading schemes

Adobe masonry is largely used as construction material worldwide and the mechanical modelling of adobe structures is a key issue. This work deals with 2-D micromechanical analysis of two component adobe masonry (i.e. composite system composed of adobe bricks and mortar joints), focusing on the influence of different bond configurations and loading schemes. Homogenization is applied by defining a periodic unit cell for each of the investigated bond schemes and by deriving global failure curves, based on failure criteria of both mortar and bricks. Experimental tests showed bi-modularity (i.e. different Young modulus in compression and tension) for both mortar and bricks, so this feature of elastic behaviour was taken into account in micromodelling. The results are twofold: for each bond scheme, critical curves in the principal stress plane are derived for the homogenised unit cell, and the relationships between the homogenised elastic moduli and the loading angle are obtained. Micromechanical analysis provided a major difference between homogenised elastic behaviour in tension and in compression. In any masonry bond scheme, homogenised elastic moduli drastically change with the loading angle.