Concrete under complex loading: mesomechanical model of deformation and of cumulative damage

The authorʹs general concept of mesomechanical constitutive modeling is applied to the description of mechanical behavior of concrete under complex loading. Concrete is modeled as a transversely isotropic composite consisting of isotropic elastic inclusions that are embedded in an isotropic plastically deforming fracturing matrix. The transverse isotropy of the composite results from the geometrical anisotropy of the configuration inclusions-matrix. The fracturing process of the matrix results in cumulative damage, in changes of Youngʹs modulus, and in volumetric expansion. The response of concrete – modeled in this way – is calculated and compared with experimental data for complex loading paths – for several combinations of compression and torsion.