单驳船沉放对沉管管段动力响应影响的物理模型试验研究

摘要

波浪作用下沉管管段和驳船的运动属于耦合运动,是极为复杂的水动力学问题.论文通过物理模型试验,研究了不规则波作用下、单驳船沉放情形下的沉管管段的动力响应问题,采用Welch方法对沉管管段动力响应进行了频谱分析,并探讨了不同波浪周期和波高情形下的沉管管段运动和缆绳张力的频谱特性.研究结果表明:与固定平台沉放情形相比,单驳船沉放情形下,不仅沉管管段低频运动周期和幅值的谱分析结果均发生改变,而且波频运动幅值的谱分析结果也发生变化.此外,还探讨了波浪条件对沉管管段运动幅值功率谱结果的影响情况,并对考虑驳船运动的沉管管段稳定性进行了研究.%Under the action of waves,the motion of the tunnel element and barge is coupled,which is a complicated hydrodynamic problem.In this paper,dynamic response of the tunnel element under random waves in the immersion of single barge is investigated with physical model experiments.Welch method is used for spectrum analysis to deal with the motion response of tunnel element,then spectrum characteristics of tunnel element motion and cable tension in different wave periods and heights are discussed.The results of spectrum analysis show that discrepancy happens not only for the low frequency motion of the tunnel element,but also for the wave frequency motion in the aspects of motion amplitude.In addition,the effects of wave conditions on spectrum analysis results of the tunnel element motion are discussed,and then,the stability of the tunnel element with single barge is studied.