The purpose of this paper is to propose a continuum micromechanics model forthe simulation of uniaxial compressive and tensile tests on lime-based mortars,in order to predict their stiffness, compressive and tensile strengths, andtensile fracture energy. In tension, we adopt an incremental strain-controlledform of the Mori-Tanaka scheme with a damageable matrix phase, while a simple$J_2$ yield criterion is employed in compression. To reproduce the behavior oflime-based mortars correctly, the scheme must take into account shrinkagecracking among aggregates. This phenomenon is introduced into the model viapenny-shaped cracks, whose density is estimated on the basis of a particle sizedistribution combined with the results of finite element analyses of a singlecrack formation between two spherical inclusions. Our predictions show a goodagreement with experimental data and explain the advantages of compliantcrushed brick fragments, often encountered in ancient mortars, over stiff sandparticles. The validated model provides a reliable tool for optimizing thecomposition of modern lime-based mortars with applications in conservation andrestoration of architectural heritage.
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