Research on Optimization of Material Transportation Scheduling for Water Conservancy Engineering Considering Emergency Response to Vehicle Malfunctions

Abstract

In-transit vehicle malfunctions during material transportation in water conservancy construction can cause delivery delays, disrupt subsequent tasks, and lead to duplicate material requisitions. To address these issues, this study develops a material transportation scheduling optimization model that explicitly incorporates vehicle-malfunction response. The model minimizes total transportation cost subject to vehicle capacity, resource compatibility, time-window, and non-duplicate-requisition constraints. Two response strategies are considered: continued transportation after on-site repair and relay transportation using an external temporary emergency vehicle. The failed task and its affected subsequent tasks are dynamically rescheduled. An adaptive hill-climbing genetic algorithm (AHCGA) is employed to coordinate transportation-batch generation, task sequencing, and resource assignment. The case study shows that, under the no-malfunction baseline scenario, all transportation batches complete unloading within their acceptable time windows. Across 30 runs, AHCGA achieves a mean total cost of CNY 9179.86; Wilcoxon signed-rank tests indicate statistically significant cost differences between AHCGA and both GA and HCGA (p < 0.001). The best AHCGA run yields a total transportation cost of CNY 8794.40 with zero total delay. Multi-scenario comparisons and sensitivity analyses further show that neither on-site repair nor external relay is universally dominant. Their relative suitability depends jointly on failed-task characteristics, on-site response and repair time, emergency-vehicle response time, transshipment efficiency, and call-out cost. The proposed model provides quantitative decision support for material transportation organization, vehicle-malfunction response, and post-malfunction rescheduling in water conservancy construction.