Abstract
Abstract : The purpose of the study was to investigate the optimal ways of reducing container terminal congestion at the Port of Durban using simulation modeling and the application of Lean Six Sigma (LSS) principles. A simulation model was used to test the “what-if” scenarios under different circumstances with the specific focus on vessel turnaround time. A comparison case was used to benchmark the turnaround time of the container terminals between the Port of Durban and the Port of Antwerp using a one sample t-test. Due to the increase in containerised cargo, several ports experience vessel congestion prior to sailing into the terminals. This resulted in various shipping liners bypassing these ports in favour of ones with higher efficiency and/or productivity rates. Several studies have been conducted to ascertain the necessity of creating increased capacity and improving the efficiencies at the ports to minimise the cost of doing business. This research explored the opportunities to prioritise the vessel turnaround time as the main determinant of the effectiveness of a port terminal in reducing container terminal congestion. The main objective of this research was to explore ways in which simulation modeling and LSS can complement each other to reduce the total vessel turnaround times thus resulting in a significant reduction in container terminal congestion. Capacity utilisation was studied as a function of the container terminal efficiency. Vessel turnaround time is used as a key measure of efficiency of the route by various shipping liners and agents for preference. This study also explored the relationship between the congestion of vessels and container terminal efficiency (vessel turnaround time). A case study for the container terminals of the Ports of Durban and Antwerp was used to help identify and understand the factors that affect the use of port capacity, the causes of congestion and what was needed to address these shortcomings. The other objective of this study was to further assess the causes of longer vessel turnaround time in the Durban container terminal. It was found that there was a positive correlation between the vessel time at berth (berth occupancy) and vessel waiting time at anchorage. The other relationship assessed was between vessel time at berth and cargo dwell time. This study found that the relationship between vessel waiting time at anchorage and cargo dwell iv time was statistically insignificant. This implied that the longer turnaround time in the container terminal was mainly caused by longer berth occupancy. It was also found that simulation of vessel turnaround time and application of Lean Six Sigma principles were effective when complementing each other to optimise container terminal efficiencies. Simulation modeling helped to understand the scale of inefficiencies prior to the selection of applicable LSS tools. After the application of LSS causes control impact matrix and subsequent simulation modeling in DCT, it was found that the vessel turnaround time of 1.68 days could be sufficient to reduce congestion.
D.Phil. (Engineering Management)