The interest in the study of the SDVRP has remarkably increased in the last years, as witnessed by the increasing number of papers on the subject. This is mainly due to the fact that allowing split deliveries can lead to big savings with respect to the classical VRP where a single visit to each customer is imposed, both in of terms travelling cost and in terms of number of vehicles used. In fact, Archetti, Savelsbergh and Speranza (2006) showed that this savings can be as large as 100%.
C. Archetti, M.W.P. Savelsbergh, M.G. Speranza. Worst-case analysis for split delivery vehicle routing problems. Transportation Science , 40, 226-234, 2006.