컨테이너 터미널의 차세대 하역시스템 성능평가

Abstract

This study aims at newly constructing and evaluating performance of the stevedoring equipment systems in container terminals. The stevedoring equipments used in conventional terminals are insufficient in flexibility in their functions or design structure, and most of the stevedoring systems based on such equipments have conventional design, therefore, limited in improving the productivity of terminals both in performance and functionality. The transportation volume in terminals has been increasing continuously in accordance with the trend of larger vessels, accordingly, the performance of the stevedoring equipment systems in terminals have been improved. However, while such improvements have been mainly focused on the operational features of terminals, which is limited in the improvement of the overall performance. This means that, it is time to devise an alternative methodology for the improvement of the stevedoring equipment systems in facilities and equipments, in addition to the operational features. Accordingly,some advanced terminals are developing high efficiency equipments and diverse stevedoring systems on the basis of the new equipment systems.

The stevedoring equipment systems in terminals, in general, can be subdivided into 4 subsystems of quay, transportation, yard, and gate system,which carry out loading and unloading works with proper facilities and equipments. In this study, a design of next generation stevedoring equipment system comprised of various stevedoring equipments which have superior performance and functionalities to the conventional equipments was proposed, and its performance was evaluated. Regarding the major contents of this study, by subsystem, 3 alternative equipments of dual trolley, double trolley, and supertainer type C/C were proposed to replace the conventional single type for the quay area, and 3 alternative equipments of two-stack vehicles, shuttle carriers, and automated lifting vehicles were proposed to replace the YT which is a conventional, simple transportation equipment for the transportation. In the yard area, RMGC(Rail Mounted Gantry Crane) is proposed to replace RTGC(Rubber Tired Gantry Crane) in order to reduce the equipment installation area. For the yard layout, both horizontal and vertical layout types were evaluated to propose appropriate equipment layout.

For the performance evaluation of the stevedoring equipment system,productivity was calculated using a simulation technique. State transition models were established for each equipment for simulation analyses. The state transition models represent each steps of stevedoring process in order to reflect the differences in the performance and function of each equipment on the analysis correctly. for the performance evaluation of the alternative system, the interconnected performance of the integrated system was analyzed as well as the unit performance of the subsystems.

For the unit performance analyses, a portion of the conventional stevedoring system was replaced with the next generation system to measure its performance. For the integrated performance analysis, the performance of the stevedoring system comprised of next generation alternatives was calculated. For the calculation of the integrated performance, scenarios were designed by combining the alternative equipments of subsystems. Each scenario was applied to horizontal and vertical yard layout plan to conduct simulation analysis.

With the simulation results, unit and integrated performances were calculated on the basis of the productivity per hour and waiting time of each equipment. Summarizing the analyses results, the proposed next generation equipments showed superior work performances to those of the conventional equipments. Number of equipments could be reduced. For the integrated performance, the stevedoring system comprised of quay,transportation, and yard was evaluated. However, these stevedoring equipment systems have merits and demerits in the performance and operation, therefore, sufficient review on design considering the working conditions of terminal is required for the design of next generation system.

The terminals in Korea have been operated without any significant change in stevedoring hardware for the last 20 years. In order to improve stevedoring productivity of terminals, the facilities and equipments should be improved and design of stevedoring system suitable for the working environment and performance analyses are required.

The simulation model and stevedoring system design are expected to be useful for the development of the next generation stevedoring system which has improved productivity and performance.