Samenvatting
This report describes a mathematical model of the arrangements for distributing different types of aggregates used for road and building construction. it is assumed that users are in free competition and, within broadly specified technological constraints, may choose which materials to use for each construction purpose. the activities of producing, transporting and using aggregates are represented as links in a generalized circulatory network. the out-of-kilter algorithm is used to calculate the flow pattern which satisfies demands for construction at minimum total cost. (Author/publisher).