Prediction of Behaviors of Floating Artificial Islands.

如果我们要实现人工岛漂浮的想法，就必须对其多年的安全性和可靠性有很高的信心。从这个角度来看，我们的研究目的是：1.提高对很长重现期内给定位置的波高极值预测的置信度。2.近岸浅水大型浮式结构物波浪力预报技术的发展。3.包括站场设施在内的多种要素组成的浮式结构体系的安全性评价。研究结果如下：1.收集了海浪资料，利用置信限的思想预测了100年的海浪。积累的数据量不足以在这一领域产生可靠的结果。(1)提出了一种计算多个基本浮体支承的浮体上的波浪力的理论方法。在这个Me…中此外，还适当地考虑了水深不均匀和海岸的存在的影响。它的理论基础是一个摄动和一个匹配的渐近，它是由结构的大小和组成它的每个元素的大小之差推导出来的；前者相当于不均匀深度的尺度，而后者相当于海底的尺度是平坦的。(2)给出了由多个圆柱体组成的结构上的二阶波浪力-漂移力的理论计算方法，并了解了这些力的特点。(1)对长柔性结构在水中的行为进行了计算机模拟，发现在设计安全设施时必须仔细考虑其非线性。(2)基本完成了模拟人工浮岛系统行为的计算机程序，包括站场保持设施等各种因素，并演示了它们的计算机图形。较少

Confidence to its safety and reliability for many years must be very high if we are to realize the idea of floating artificial islands. In this perspective the objectives of our research were: 1.Improvement of confidence to the prediction of extreme values of wave heights at a given location in very long return period. 2. Development of the prediction technique of wave forces on large scale floating structures located at shallow water close t o the coast. 3. Evaluation of safety of a floating structure system composed of a lot of elements including the station keeping facilities. Results of the research were: 1. We collected wave data obtained Genkai-nada area and predicted 1 00 years waves with taking into account the idea of confidence limits. The amount of data accumulated is not sufficient to have the reliable results in this area.2. (1) A theoretical method was developed for predicting wave forces on a floating structure supported by a lot of elementary floating bodies. In this me … More thod the effects of non-uniform depth of water and the existence of the coast are appropriately considered. Its theoretical basis is a perturbation and a matched asymptotic deduced from the difference between the structure's size and the size of each element composing it; the former is of th e order of kilometers comparable to the scale of non-uniform depth while to the latter's scale the sea bottom is flat. (2) A theoretical method to calculate second order wave forces, drift forces, on a structure composed of a lot of circular cylinders was given and the characteristics of these forces were understood.3. (1) A computer simulation of the behaviors in the water of long flexible structures, which would be used as elements of the stationkeeping facility of the structure, was studied and it was found that their nonlinearity have to be considered carefully when designing the safe facility. (2) We almost completed a computer program to simulate the behaviors of the artificial floating island system including various factors such as the station keeping facilities and to demonstrate their computer graphics. Less