  We present a reduced-dimension, ballistic deposition, Monte Carlo particle
packing algorithm and discuss its application to the analysis of the
microstructure of hard-sphere systems with broad particle size distributions.
We extend our earlier approach (the ``central string'' algorithm) to a
reduced-dimension, quasi-3D approach. Our results for monomodal hard-sphere
packs exhibit a calculated packing fraction that is slightly less than the
generally accepted value for a maximally random jammed state. The pair
distribution functions obtained from simulations of composite structures with
large particle size differences demonstrate that the algorithm provides
information heretofore not attainable with existing simulation methods, and
yields detailed understanding of the microstructure of these composite systems.
