Exact methods based on node routing formulations for arc routing problems

This paper proposes a new transformation of arc routing problems into equivalents node routing problems, with emphasis on the transformation of Capacitated Arc Routing Problems (CARP) into Capacitated Vehicle Routing Problems (CVRP). For this last case, an analogue transformation has already been proposed in Pearn et al. [21], where each required CARP arc was mapped onto a triplet of CVRP nodes. In our case, only 2 CVRP nodes are needed for every CARP required arc. The transformed instances have a structure and a dimension which make most CARP benchmarks solvable by state of the art CVRP techniques. We thus propose a general purpose transformation of arc into node routing problems and new results on lower bounds and exact methods for CARP instances. . DISMI, University of Modena and Reggio Emilia, Viale Allegri 13, 42100 Reggio Emilia, Italy. . Department of Computer Science, University of Bologna, Mura Anteo Zamboni, 7 40127 Bologna, Italy. 1