A gauge modification-based railway out-of-gauge freight transportation route decision-making methodology

The loading outline of railway out-of-gauge freight (ROF) is beyond the railway gauge due to its larger size. The choice of a safe and economical transportation route according to the characteristics of the freights in the railway network becomes an important issue for the railway out-of-gauge freight transportation. A proposed methodology is presented in this paper with the aim to solve the problems in the railway out-of-gauge freight transportation route decision-making (ROF-TRD) process in which safety distances between the railway gauges and freight loading outlines, the curve radius and the arrival-departure traffic flow balance are taken into consideration while the railway capacity losses and transportation costs being as objective functions to construct the route decision-making model considering gauge modification. The proposed route search algorithm can be used in the model to further refine the design of an effective safety distance bilateral detection. The case study verification shows that the safest and most economical railway out-of-gauge freight transportation route can be obtained by applying the proposed model, and the results demonstrate that taking railway capacity loss and modified costs of possible ROF routes into consideration, the optimal route can save around 10–22 % of total costs.