STOCHASTIC MODELING OF INLAND NAVIGATION LOCKS: A MONTE CARLO FRAMEWORK FOR CONVOY LOCKAGE AND CAPACITY ASSESSMENT

energy consumption, and effective lock capacity. This study develops a stochastic modeling framework for inland lock operations based on Monte Carlo simulation. The lockage process is decomposed into elementary operational stages, including maneuvering, mooring, gate operations, hydraulic processes, and convoy reconfiguration. The model is applied to the Bariri lock on the Tietê-Paraná Waterway, Brazil, where standard BP2x2 convoys must be temporarily dismembered into two BP1x2 units due to chamber width limitations. The simulation results show that total lockage time ranges approximately from 6 to 7 h depending on operational conditions, and that effective annual lock capacity may vary by about 15-17 % across the analyzed scenarios. The sensitivity analysis identifies mooring time as the dominant operational factor controlling lockage-time variability. In addition, differences between the most and least efficient scenarios correspond to approximately 120 L of fuel per lockage, which may represent annual savings of about L of fuel and nearly 960 t of CO2 under typical operating conditions. The proposed framework demonstrates how operational variability propagates from local lockage procedures to system-level indicators such as reliability, energy consumption, emissions, and infrastructure throughput. The methodology is transferable to other inland waterway systems and supports evidence-based operational planning and capacity assessment.