当柱稳式平台的气隙计算结果为负值时,需要对该平台进行气隙评估,其中包括波浪水平载荷的计算分析。在工程设计技术基础上,依据相关规范方法,总结出一套工程实用方法,以改进柱稳式平台局部结构的加强设计。典型案例选取某柱稳式平台的前舱壁模型,计算平台局部上浪抨击载荷,并通过有限元方法进行平台前舱壁受波浪抨击载荷下的瞬态时域计算,最终得到前舱壁在波浪抨击载荷下的应变及变形。计算结果表明,水平波浪冲击载荷对于甲板箱垂直表面产生较为严重的破坏,不可忽视。应基于数值计算结果,对局部结构进行加强设计,直至设计符合相关规范要求。
When the air gap of the column stabilized units turns out to be negative, the evaluation for the consequences of the negative air gap is needed, which includes the calculation of horizontal wave impact loads. According to the method of engineering design and the related international codes, a practical method is proposed for the engineering design of the column stabilized units. As a demonstration, the forward bulkhead of a certain column stabilized unit is analyzed. The wave impact loads on the local structure is calculated and the transient simulation is performed by means of the finite element method (FEM). Finally, the strain and deformation in the forward bulkhead under the horizontal wave impact loads are obtained. The results show that the effect of horizontal wave impact loads on the vertical surface of deck box cannot be ignored. Thus, once the air gap of the column stabilized units is negative, the horizontal wave impact loads on the vertical surface of deck box must be fully considered. The local structure should be reinforced and re-analyzed based on the simulation results until the design meets the rules and standards.
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