Abstract
A computer program cosmos which estimates the construction costs of roads has been developed at the transport and road research laboratory. The program is intended for use in the design of roads to cost particular alignments and for incorporation into alignment optimisation programs. This report describes models within cosmos for estimating the costs of highway drainage and culverts. Tests are described which have shown that the accuracy of the models in estimating costs is similar to that of the other models that make up program cosmos. The program also allows the costs of alternative designs to be assessed quickly. (Author/publisher)