起重船近海风电场坐底施工作业分析

Operation analysis on the on-bottom construction by a crane vessel in a nearshore wind farm

以起重船“三航工5”为例,结合某海上风场环境条件,对不具有坐底相关入级符号的起重船坐底施工作业及坐底全过程所涉及的技术问题进行分析,并对锚固定位和坐底稳性进行计算,采用经验公式计算波流荷载、频域边界元方法计算波浪力。计算结果表明,“三航工5”在淤泥底质条件下,需要在流速小于1.3 m/s的条件下进行下潜或上浮作业,以避免走锚;为满足坐底稳性要求,需要初始超加压载水达到4500 t,后降至2500 t。

Taking the crane vessel Sanhang Gong 5 as an example,combined with the environmental conditions of a certain nearshore wind farm,the technical problems involved in the construction and the whole process of the on-bottom setting of the crane vessel without relevant classification symbols were analyzed.The anchoring positioning and on-bottom stability were calculated.The wave current load was calculated by empirical formula and the wave force was calculated by using the frequency domain boundary element method.The calculation results show that under the condition of silt bottom material,the Sanhang Gong 5 needs to dive or float under the condition of velocity of flow less than 1.3 m/s to avoid anchor moving,in order to satisfy the on-bottom stability requirements,the initial amount of ballast water extra should be 4500 t,and then reduced to 2500 t.