This report discusses the application of optimisation to the design of highway vertical alignments. It describes the background to and the development of a computer program Minerva which uses an optimisation technique of the hill- climbing type to make adjustments to a vertical alignment in order to minimize construction cost. The basic element of construction cost considered is that for earthwork. Constraints on the alignment such as design standards, level restrictions and 'phasing' of curves are observed. The program operates throughout with vertical alignments defined in the conventional manner by straight lines and parabolic arcs, and so produces optimised alignments which are immediately usable by highway engineers. An extensive programme of tests has demonstrated that a saving of about #2 million per annum could be achieved if the program was used on all Britain's motorway designs. Minerva is to be made freely available to highway designers through the highway engineering computer branch of the department of the environment during 1972. Instructions for preparing the data for the program are contained in a user's manual to be published separately from this report. (Author/publisher)
Abstract