沉垫型自升式平台拖航状态强度分析

Strength Analysis of the Mat Supported Jack-Up Platform in Transit Condition

采用势流理论 ,考虑辐射和绕射的影响 ,计算了作用在平台上的波浪动压力 ,并定义了三组设计波 ;基于有限元模型计算得到了主船体、沉垫、桩腿和固桩架等结构在设计波下的应力分布 ;分析了沉垫型自升式平台拖航时的载荷与结构响应特点 .结果表明 ,沉垫在斜浪下的结构响应是平台拖航可行性的制约因素 ;在拖航状态中 ,桩腿最危险部位在沉垫和主船体之间 ;在满足平台稳性的前提下 。

The wave dynamic pressures acting on the platform were calculated by use of the potential theory considering the effect of radiation and diffraction. And the three groups of design waves were defined. The stress distribution of the main hull, the mat, legs and jack houses was obtained on the detailed finite element model. The character of loads and structural response of the mat supported jack-up platform in the transit condition was described. The computational results indicate that the structural response of the mat in the oblique wave is the constrained factor of the feasibility for the transit. The critical areas legs in the transit condition locate between the main hull and the mat. The results also show that the structural strength of the platform in the transit can be dominantly improved if the mat is suitably lowered on the premise of keeping enough stability of the platform.