1. OPI definition

1.1 Principles

The formulation of the BPR is guided by the following principles:

• the mechanical effects induced by the heterogeneity of the granular components of conventional concretes are greatly reduced by the elimination of coarse aggregates and the significant improvement in the mechanical properties of the binder paste;

• the introduction of components of different granular classes, respecting the principle of loosening, according to which fine aggregates occupy a volume greater than the void index of aggregates of a higher class, minimizes the overall void index of the material and the quantity of water required for mixing;

• the use of small, high-strength metal fibers...