Inland Waterway Transport (IWT) is an untapped resource that can be mobilised to achieve a more sustainable transport system without compromising competitiveness. It outperforms rail and road alternatives in terms of low emissions, costs, high capacity, energy efficiency, freight safety, and security. Waterway locks are ageing assets in IWT systems and are infamous for creating bottlenecks. The effectiveness and performance of these locks can be measured and integrated into decision making to establish well-informed operational, maintenance, and renewal policies. This study addresses the following research question:How can the effectiveness of waterway locks be assessed to support lock maintenance and operation? Simulation modelling, which offers an efficient and low-risk evaluation of policy options while incorporating the intrinsic variability of the system, is selected as the core methodology. The simulation model incorporates operational aspects of the system, malfunctions, corrective maintenance activities, and the calculation of various performance indicators. An extensive list of performance indicators is complied through literature research. These indicators include infrastructure occupancy, vessel waiting times, costs, and emissions. In addition to existing indicators, three formulations for Overall Equipment Effectiveness (OEE) are proposed in lock complexes. The applicability of the selected methodology is demonstrated by employing a case study of the Volkerak complex, one of the largest and busiest lock complexes in Europe. Quantitative and qualitative data, collected through operational logs, maintenance reports, and interviews with experts, support that as the lock complex gets older, malfunctions become more frequent. SIVAK, a software package utilised by the Ministry of Infrastructure and Water Management of the Netherlands ("Rijkswaterstaat", RWS), is used as the basis of the simulation model. Extensions are made to calculate additional performance indicators and to simulate fluttering doors and slowdowns, two types of malfunctions that are diagnosed to be frequent and impactful based on maintenance reports and interviews. Experiments are designed to explore the performance of different maintenance policies, such as mean time to repair (MTTR) and inspection frequency, and different operational policies such as locking regimes under various fleet mix and lock condition scenarios. Stress tests and univariate analyses are also conducted. The study findings highlight the following: - With rising demand, the significance of lock condition in maintaining acceptable service levels and minimising CO2 emissions becomes more evident. The findings indicate a trade-off between preventive and corrective maintenance efforts. In challenging lock conditions, faster repairs and more frequent inspections are needed to prevent capacity problems, leading to longer waiting times. Notable differences in handling capacity are observed in the three lock conditions studied. - The concept of baseline OEE proves to be valuable as a maintenance-oriented metric. It emphasises that proficient maintenance strategies can counteract deficiencies in the lock system, resulting in improved capacity, reduced transit times, and reduced CO2 emissions. A general rule of thumb suggests that improving baseline OEE by one point corresponds to about a 1.2%-1.5% improvement in waiting times and emissions. - Changing MTTR and inspection policies influences baseline OEE scores, but these adjustments must be aligned with the lock condition. Frequent inspections might yield unnecessary availability losses when the lock is well maintained. Similarly, the extent of benefits of shorter MTTRs depends on the frequency of breakdowns. - A prominent dilemma in lock systems involves balancing transit times and the number of levellings. Locking regimes capture this trade-off, where reducing waiting time thresholds increases levellings and operational costs. However, some strategies can achieve an improvement in both aspects. These include expanding traffic range and considering the current state of the system when assigning lock chambers to incoming vessels. - Service-based OEE, integrating operational and maintenance policies, aligns better with waiting times and CO2 emissions compared to the service level alone. This composite index can serve the purpose of monitoring waterway network lock systems, helping to identify losses due to unavailability and reduced speed.

Port planning is a complex multidisciplinary subject. To fulfill its functions, it is essential that the different elements of a port work together. The full potential of a terminal can only be reached when the wet infrastructure of a port (access channel, inner basins, turning circles) can keep up with the traffic load. From the literature study, it has become apparent that simulation tools have become increasingly popular for assessing the capacity of ports and waterways. However, the application has often been aimed at a specific case study and the existing models are not easily reusable for new applications. In this master thesis project, the assessment through a generic simulation tool of the effective capacity of the wet infrastructure of a port is investigated. The model considers the processes taking place from the point a vessel arrives at the entrance of the access channel until the start of the (un)loading procedures and the departure of the port until exiting the access channel. The analysis capabilities of the model are demonstrated by studying the Port of Hazira. The main processes of the model relate to vessels obtaining authorisation to sail towards a destination. To receive this authorisation, the vessels must find a moment when the correct weather conditions occur, the tidal elevation is adequate, the waterways are available and sufficient quay length is available. The authorisation is given in a dynamic way, depending on the dimensions of the vessels, waterways and quays. Based on their origin and destination, vessels can determine their route based on the shortest path available and waterways available depending on their vessel type. Once this is done, a vessel will construct a sailing plan by finding a suitable timeslot to through each section of the port. When doing so, a vessel takes into account the sailing plans of other vessels and the sailing rules that apply for each section. As a result, a vessel can construct a suitable sailing plan based on an origin and destination which can be applied to any port layout. During this study, it has become apparent that many processes should be included to properly determine the capacity of port. Simulation software offers the possibility of including all these processes and observe their interactions in order to locate bottlenecks more efficiently. Simio has proven to be able to incorporate all the required process to properly model the wet infrastructure of a port. However, it does not offer a user-friendly interface to handle different scenarios and facilitate the handling of both the input and output of the model. To this easier, an interface has been created with Scenario Navigator. This interface enable the storing and comparing of input parameters and results of different scenarios.