An earlier paper described a model by means of which average travel times with alternatives geometrical forms of motorway (freeway) network could be evaluated. The paper was mainly concerned with rectangular grids of motorways, with possibly unequal spacings in the two directions, but it was possible to deal mathematically with only certain special cases. The present report describes a computer simulation which provides estimates of the average travel times for more general values of the various parameters. For likely values of the parameters, and with a fixed length of motorway per unit area, it is found that square grids are better than systems with larger spacings between motorways in one direction than between those in the other. Only for extremely fast motorways or for extremely long journeys would the latter have any advantage, and even then it would only be slight. Over most of the range of the variables covered, a square network gives the lowest ratio r of average travel time with a motorway network available to average travel time using ordinary roads only. /Author/
Samenvatting