Long-term field measurement of a Very Large Floating Structure and development of a rational design method

本研究以淡路岛大型浮式结构物为研究对象，进行了波浪响应的长期实测。测量了系泊船舶的垂向弹性响应和水平运动，并与模拟值进行了比较。在频域中比较了垂向水弹性响应，得到了很好的一致性。在时域内对水平运动进行了数值模拟，考虑了系泊恢复力的非线性特性和记忆效应，通过调整护舷间隙，得到了较好的一致性。本文的模拟基本上可以代表实测值，但还需要进一步改进，以考虑多向不规则海况。2006年，根据现场实测的流速和水压测量值再现了多向不规则波。测量了系泊船舶的水平运动，并与频域模拟值进行了比较。结果表明，当考虑多向不规则波时，水平运动的有意义值与实测值吻合较好。

In this research, the long-term field measurement of wave response of a large floating structure located at Awaji-island was made. The vertical elastic response and the horizontal motion as a moored vessel have been measured, and compared with the simulated values. The vertical hydroelastic responses have been compared in the frequency domain, and a good agreement has been obtained. The horizontal motion has been simulated in the time-domain where the nonlinear mooring restoring force characteristics and the memory effect are considered, and also a good agreement has been obtained, if the clearances at the fenders are adjusted. Basically, the simulation presented in this paper can represent the measured values; however, further improvement to consider the multi-directional irregular sea-state may be necessary.Then, in FY 2006, the multi-directional irregular waves have been reproduced from the measurement values of current speed and water pressure obtained from the field-measurement. The horizontal motions as a moored vessel have been measured and compared with the simulated values in frequency domain. The results have shown that the significant values for the horizontal motions by the simulation agree well with the measured values, when the multi-directional irregular waves are considered.