锚泊安全视域下的锚链振动特征检测实验研究

Experiment study on vibration characteristics of anchor chain from the perspective of anchorage safety

锚链振动特征检测研究旨在解决舰船走锚预警问题。利用专门实验装置模拟舰船走锚过程,实时检测锚链振动加速度,并采用Matlab编制的专用程序对进行耦合计算等处理,进而得到锚链振动特征值并输出相应的曲线图形。实验结果表明:在锚链绷紧、锚翻出底土、跳锚、走锚等状态下,锚链振动频率会发生突变。相同锚泊环境下,底质、船重~锚重比、链重均对锚链振动特征有影响:锚链振动频率突变极值越大且次数越多时,舰船越难走锚;泥沙底的突变频率平均极值为砂砾底的1.1~1.4倍;随着链重的增加,锚链振动平均频率和突变频率平均极值均随之增大,舰船从正常锚泊演变到走锚的时间变长,锚链振动频率突变的次数也越多。结论可为舰船锚泊安全状态监测及走锚预警深入研究提供参考依据。

The vibration characteristic detection of anchor chain is used to solve the early warning of ship dragging.A special experimental device was used to simulate the process of ship dragging,the vibration acceleration of anchor chain was detected and its vibration frequency was calculated.The experimental results show that the vibration frequency of anchor chain changes significantly in the state of anchor chain tension,and anchor turning out of subsoil or dragging.Under the same anchoring environment,anchor chain’s vibration characteristics are impacted by bottom substrate,ratio of the anchor weight to that of the ship,and the quality of anchor chain etc.The higher the mean value of maximum vibration frequency of anchor chain is,the more difficult it is for ship dragging.The mean value of maximum vibration frequency in sand bottom is 1.1-1.4 times than that in gravel bottom.With the increase of chain quality,the mean vibration frequency and the extreme value of surge frequency increases,the time from normal anchorage to dragging becomes longer,and more times the frequency changes significantly.The conclusion can provide references to further research on monitoring anchorage safety status and early warning of ship dragging.