The aim of this study is to present a model for assessing the dynamic compression behaviour of a micro-concrete. This model is based on the results of numerous tests providing the developments of the mechanical characteristics of the material on a wide range of strain rate from 10-4s-1to 10+3s-1.The Split Hopkinson Pressure Bar (SHPB) dispositive, based on the wave propagation theory in materials, has-been adopted to carry out the dynamic tests on the investigated material. The proposed model is composed of two terms, each characterizing the different contributions noted in the two major explored areas of strain rate.

The main idea of this paper is to present a smart numerical technique to solve structural and non-structural problems in which the domain of interest extends to large distance in one or more directions. The concerned typical problems may be the underground excavation (tunneling or mining operations) and some heat transfer problems (energy flow rate for construction panels). The proposed numerical technique is based on the coupling between the finite element method (M.E.F.) and the infinite element method (I.E.M.) in an attractive manner taking into consideration the advantages that both methods offer with respect to the near field and the far field (good accuracy and sensible reduction of equations to be solved). In this work, it should be noticed that the using of this numerical coupling technique, based on the infinite element ascent formulation, has introduced a more realistic and economic way to solve unbounded problems for which modeling and efficiency have been elegantly improved. The types of the iso-parametric finite elements used are respectively the eight-nodes (Q8) and the four-nodes (Q4) for the near field. However, for the far field the iso-parametric infinite elements used are the eight-nodes (Q8I) and the six-nodes (Q6I).