ABSTRACT
The packing density of a granular mix is defined as the solid volume <I> in a unit total volume. Alternatively, the compaction may be described by the porosity:
or by the voids index:
7T 1 e = - = --l (1.2)
The prediction of the packing density of a granular mixture is a problem of extreme relevance for concrete (Johansen and Andersen, 1991), but it is also relevant in many other industrial sectors (Guyon and Troadec, 1994). Many composite materials, like concrete, are made up of granular inclusions embedded in a binding matrix. The aim is often to combine grains in order to minimize the porosity, which allows the use of the least possible amount of binder.
