Study: Moored Ship Behavior

During the 53rd Naval Engineering Spanish Congress, Siport21 has presented the results of a project to characterize the behavior of the moored ships in the Outer Port of A Coruña, using “GPSFlot”. A sophisticated GPS RTK system was used to measure the motions of moored vessels in six degrees of freedom with a high degree of accuracy. This equipment was developed by Siport21 as part of a R+D project. 

This study, which also had GEAMA and Aquatica Ingenieria Civil in the research team, had the aims of to establish limiting operation conditions, quantify the availability of the terminals and evaluate the impact of future modifications on the layout. A measurement campaign was therefore established in order to correlate the maritime and weather conditions and the movements of the ships. The instrumentation used included different measurement elements, comprising wave sensors, radar, ADCPs, anemometer, strain gauges for the mooring lines, etc. 

A “test ship” was moored in one of the berths during a 3 months period, so that many different environmental scenarios could be recorded during winter. On the other hand, measurements continued in order to cover the operation of several different ships. 

From the data obtained different analyses were carried out in order to characterize the behavior of the vessels (statistical analysis, spectral analysis, time series analysis, etc.) A multi-variable model was built based on the recorded data so as to correlate ship motions with the main environmental parameters (wave height and period, long waves, wind speed and direction, tidal level, etc.) 

Finally, a time domain numerical dynamic mooring model was calibrated with the recorded data to forecast the behavior of the vessels in different meteorological conditions and in future layouts of the port (development of additional sheltering structures or berths). 

This project follows the line of innovation and the cutting-edge marks by the company, which was recently awarded the 2014 Prize for the best company related to naval and maritime sector by Spanish Naval Engineering Association.