中文摘要：

针对强台风引起的极端波浪载荷,采用非线性动力分析方法,考察两座深水导管架平台在弹塑性响应阶段的动力特性及承载能力。研究表明,两座平台在弹性阶段均存在不同程度的动力放大效应,且越接近非线性响应阶段,动力放大效应越显著。进入弹塑性响应阶段后,平台A的动力放大效应更加显著,而平台B却不存在动力放大效应,这说明平台结构的塑性变形会导致其动力特性发生改变。平台A在动环境载荷下的极限承载能力小于Pushover分析得到的结果,而平台B的动极限承载能力大于Pushover的结果,表明环境载荷的动力特性影响着平台结构的极限抗力。因此,建议对深水导管架平台应采用非线性动力分析评价其位移响应与承载性能。

英文摘要：

In view of the issue of extreme wave load caused by the strong typhoon on fixed offshore structures, dynamic performances of two deepwater jacket platforms in elastic-plastic response phase and their ultimate bearing capacities are investigated by using nonlinear dynamic analysis method. The results show that there are dynamic magnification effects for both platforms in the elastic response phase, and when near to the nonlinear response phase, the dynamic magnification effect （DAE） is more significant. In the elastic-plastic response stage, the DAE of platform A is significant, but platform B has no DAE, which means that the plastic deformation of structures may change the dynamic characteristic of the platform. From the view of ultimate bearing capacities of the two platforms, the results illustrate that the dynamic ultimate bearing capacity （DUBC） of platform A is less than the static ultimate bearing capacity （SUBC）, while platform B＇s DUBC is larger than SUBC. This indicates that the environmental dynamic load impacts on the structural ultimate bearing capacity. Therefore, it＇s necessary to apply nonlinear dynamic analysis in evaluating the ultimate bearing capacity of deepwater jacket platforms whose dynamic characteristic are more significant.