For shielding type or armor applications, it is important to know the state of the material well after the passage of the divergent spherical wave which comes off in front of the impactor projectile. The objective of this chapter is to present an experimental technique which make it possible to load materials in a large range of dynamic strain and stress: The Spherical Expansion Shock Wave Pyrotechnic Test. The paths of loading, the observed micro-physical phenomena and the associated behaviors of two brittle materials (two ceramics) are described. A particular focus is made on the influence of the microstructure and the nature of the ceramic on their dynamic behavior. Numerical simulations are presented. Some of them give the history of the states of strain and stress as well as contribute to the understanding of the physical phenomenology; the others report on the experimental mechanical behavior of these ceramics. This chapter show that is important to consider the state of the material after being submitted to an initial divergent spherical wave before modelling the mechanical response of the material in a shielding type structure. These analyses allow to better consider physical phenomena in the mechanical behavior modelling and so the improvement of the mechanical strength/density ratio of the constituent materials of these kind of structures.