A simple concrete-based structure model is proposed by developing it from nano to macro structure. In this model, the structure is divided into four levels and each level is represented by a parametric model. The parameters of the four based structures are identified, in terms of elastic modulus (EM) and poisson’s ratio at any time period (t) at Calcium silicate hydrates (CSH), cement paste, mortar and concrete levels. Then, by integrating the proposed model with Bazant – Baweja (B3) model, the compressive strength (CS) and EM of concrete at different curing periods is estimated. Further, it is analyzed and validated by other international models such as B3 model alone, Comite Euro – International Du Beton (CEB) model and Indian standards (IS) method. Few tests were done to investigate the CS of concrete with the inclusion of 25% fly ash (fa) and varying ratios of waste foundry sand (WFS) – 0, 25, 50, 75 and 100%. The results are compared with the obtained values by other models and validated with the experimental results. It is found that the proposed model (PM) i.e., Multiscale modeling (MS) can be used reliably integrated with the other models and builds the interaction between the various matrix to estimate and study the strength parameters of the concrete. MS is a new technique which is based on the mathematical formulation, it doesn’t require any earlier data about the mechanical properties of the concrete except the intrinsic values of the cement-based materials and mix details to evaluate the strength of the concrete. © 2020, Fundatia Serban Solacolu. All rights reserved.