Abstract Earthwork Allocation and Transportation (EAT) significantly impacts construction cost in Railway Alignment (RA) optimization, but slight research has been devoted to this problem. To this end, an RA-EAT bi-level optimization framework is developed. A concurrent RA-EAT design model is formulated at the upper-level. At the lower level, the EAT system is modelled by incorporating earthwork allocation sections partition, soil waste/borrow pits selection and access roads generation. To solve this bi-level model, a tailored solution strategy is proposed. Specifically, a candidate pool for borrow/waste pits is established via a moving window method. Then, RA alternatives are generated using a Particle Swarm Optimization (PSO). Afterward, the EAT model is solved with a hierarchical approach, including determining EAT sections along an RA with a divide-and-conquer method and configuring access roads with a modified Dijkstra's algorithm. Thus, the total RA-EAT solution can be iteratively evolved through the PSO rationale. Finally, the proposed method is verified and analyzed in a real-world case via a sensitivity analysis and a comparative experiment.
Pu et al. (Wed,) studied this question.