Container Terminal Wind System

When the wind speed gets too high, container handling operations need to be shutdown. CP&A provided back end development of a system capable of real-time calculation of critical wind speeds based on actual stacking configurations. Dynamic monitoring of stacking configuration and weather conditions can provide more realistic warnings.

During our research, we found that the wind speed which causes containers to fall is sensitive to the stacking configuration and the laden weight of the containers.  Another sensitive variable is the wind direction. Any attempt to find a single shutdown speed requires a lot of assumptions and will likely be overly conservative for many scenarios. To get the most efficient and realistic wind shutdown policy, active calculation of critical wind speed for all the containers in the pod based on their stacking arrangement was studied.

Because container stability is sensitive to the sliding coefficient of friction between containers, a test of the container friction under various weather and site conditions was performed.  The friction factor between the containers does change with wet conditions and when dust is present. These factors were integrated into the critical wind speed calculations, where the weather conditions can be read from an outside source so an appropriate shutdown wind speed can be determined. The systems integrator was able to link the inputs to a weather forecasting service so the conditions automatically update reflect the weather. The stacking configuration, container dimensions, and container weights are determined from data output by the Terminal Operator's existing TOS system.

This benefits terminal operations by estimating more realistic warnings for the as-stacked containers instead of using worse-case scenarios. When this information is combined with wind monitoring and forecast data, shut-down decisions can be made with more precision and confidence. Operation personnel will be able to determine which containers are adversely influencing the critical wind speed, thus allowing re-stacking operations to improve the critical wind speed while maintaining the same level of safety. Integration of a weather forecasting system from a nearby University helps operation personnel with planning, scheduling and decision-making involving container operations in windy conditions.