To reduce the contradiction between increasingly congested traffic and high time-sensitive freight delivery demand, this study develops a combined subway-and-city-freighter (CSC) operation strategy. Considering the capacity limitation of the subway train and city-freighter, the train departure schedule, and waiting time of demands at transshipment station, a routing optimization model in CSC urban distribution system is proposed. Our proposed model can be used to address urgent logistic issues that include demand assignment of transshipment stations, demand assignment of subway trains and arrangement of vehicle routing. This model can minimize the total cost including fixed cost, delivery cost, wait cost and arrival time cost. Then, we design an Iterated Local Search with Randomized Variable Neighborhood Descent (ILS-RVND) algorithm as well to numerically solve this model. Chromosome representation, one important step of the ILS-RVND algorithm consists of two parts: demand assignment of subway trains and arrangement of vehicle routing. Each part covers the demand assignment of transshipment stations. Based on this, a new initial solution construction method is designed, as well as special local search operators and perturbation. Experiment analysis is conducted to validate the model and algorithm by using a real case study in Chengdu, China. By comparison of experiment results, the CSC urban distribution scheme and truck distribution scheme are respectively evaluated based on two scenarios of a road network and a single subway line in Chengdu. These results demonstrated that within a certain range, the CSC urban distribution has high punctuality and low total cost, which can provide better services than individual delivery of trucks.

CICTP