Evaluation of the LDPM elastic and fracture parameters by up-scaling procedure

The heterogeneity of the concrete may be considered on different size scales of observation, ranging from the atomistic scale (10-10m), characterized by the behavior of crystalline particles of hydrated Portland cement, to the macroscopic scale (101 m), where concrete has traditionally been considered homogeneous. The multiscale framework we are proposing in this paper is based on the following models: chemical analyses at the cement paste scale; mechanical lattice model at the cement and mortar scales; geometrical aggregate distribution models at the mortar and concrete scales; and the Lattice Discrete Particle Model (LDPM) at the concrete scale. For that purpose, a set of analysis starting from a known set of parameters of the cement paste. This input is utilized to evaluate the mechanical properties of the mortars (cement and sand), and then these properties are used to evaluate the mechanical properties of the mortar-a4 (mortar-s and aggregate smaller then 4mm). The upscaling in the proposed methodology involved the evaluation of the LDPM concrete parameters based on the mortara4 properties. Here we are suggesting a uni-axial tension" numerical experiments" on the mortar-a4 scale to evaluate the elastic and fracture LDPM mechanical parameters.