Architecture for designing robust road networks

The road network in the Netherlands and in many other countries is becoming more and morevulnerable. Small disturbances can cause major disruptions on large parts of the network. In thispaper a new network design method is presented which focuses on improving the robustness andtherewith reducing the vulnerability of a road network. This method consists of a specification ofthe design standards, a functional analysis of the road network, a design process and a test of thequality of the robust road network design. These steps could be used to design a robust roadnetwork for any area. In this paper these steps are worked out in detail for the network of 2020 ofthe area The Hague – Rotterdam in the Netherlands to demonstrate how the method works. Acomparison of the new robust network design with the policy network of 2020 showed that ingeneral the robust network performs better in the situation with and without disturbances. Thetotal travel time is 2.3% lower, the total distance travelled is 0.8% lower and the average networkspeed is 1.6% higher. Furthermore, the average number of vehicle loss hours in the case ofaccidents is 29% lower, the standard deviation of these vehicle loss hours is lower as well andvehicle loss hours are less extreme. Therefore, it is concluded that the presented design methodmakes it possible to improve the robustness of a road network