船行波作用下桥梁浮式施工平台动力响应分析

为研究船行波对浮式平台动力响应的影响，以国内某桥施工中设计的浮式平台为研究对象，使用海洋工程有限元分析软件 USFOS 建立了包含龙门吊在内的浮式平台模型，分析了浮式施工平台对波浪周期的敏感性，并研究了船舶航速以及船行波入射角度对浮式平台动力响应的影响。结果表明: 波浪周期对浮式结构动力响应影响很大，浮式平台自振周期应尽量远离船行波周期，以降低平台动力响应; 船舶航速增高会使波高、周期增大，设计航速应考虑浮式结构在波浪荷载下的动力响应影响; 船行波浪入射角度对该类结构的动力响应影响较大，按照 0°的入射角进行动力响应分析会低估船行波浪荷载影响。此研究成果对浮式施工平台的设计及施工具有一定的指导意义。

Dynamic response analysis on floating construction platform under effect of ship-generated wave

In order to study the impact from the dynamic response of the ship-generated wave on the floating construction platform，a model of floating platform with gantry crane is established with the marine engineering finite element analysis software— USFOS by taking a floating platform designed during the construction of a bridge in China as the study case，and then the sensitivity of the floating construction platform to wave cycle is analyzed，while the impacts from ship sailing speed as well as the incident angle of the ship-generated wave on the dynamic response of the floating platform are analyzed herein． It is concluded that the impact from the wave cycle on the dynamic response of the floating structure is quite large，thus the self-vibration cycle of the floating platform is necessary to be far away from the ship-generated wave cycle as far as possible，so as to lower the dynamic response of the platform． Increasing ship sailing speed can make the wave height and cycle be increased，and then the impact of the dynamic response of the floating structure under wave load must be considered during the design of ship sailing speed． The impact from the incident angle of the ship-generated wave on such type of structure is larger，thus the impact from the load of the shipgenerated wave can be underestimated if the analysis of the dynamic response is carried out in accordance with the incident angle of 0°． The study made herein has a certain referential value for the design and construction of the floating construction platform．