| Variability of offshore platform structure and the complexity of the marine environment which makes vibration control of offshore platform structure issues become very important. To meet the durability and safety of normal use of the platform structure under different disasters, the paper made a dynamic analysis of offshore platform which applied of MTMD, made main research of seismic performance and resistance to ice of new offshore platform structure system based on rocking column, characteristics of this new architecture is derived by compared with traditional pure steel truss, and gives appropriate design proposals. The main works are as follows:1. For JZ20-2 offshore platform structure, proposed a new measure that MTMD be applied to the offshore platform’s deck for structural damping. In full knowledge of the characteristics of the platform structure, dynamic response characteristics, choose a one-way sliding TMD, and the multiple tuned mass dampers(MTMD) be connected with offshore platform structure via a parallel form. Parameter optimization of MTMD which be applied on offshore platform has been studied. The results showed that, MTMD has a certain effect on controlling the vibration response of offshore platforms, but the damping range is limited, an less robust.2. For JZ20-2 offshore platform structure, proposed a new offshore platform structure system based on rocking column, and its performance made the finite element analysis. Including optimize the rocking column’s mass, stiffness and other parameters. The results showed that this new form of rocking column structure can be applied effectively in control of the platform structure, to avoid deformation of the jacket concentrated phenomenon, improve energy dissipation capability of the offshore platform under marine seismic and ice-induced loads, and has a good robustness; rocking column’s quality and stiffness parameters have a greater impact on the structural dynamic response. From the analysis results and economic point of view, the scope of rational optimization can be determined.3. On the basis of the new offshore platform structure system based on rocking column, this paper optimized the different programs and specific parameters of the connecting rod between offshore platform and rocking column. The results showed that, the connecting rod has a certain effect on reducing the damping of offshore platform, can be determined of the optimum number, rigidity and the theoretical value of connecting rod by the results.4. Proposed a new form of the damper of angular displacement, will be applied to offshore platform structure system based on rocking column. Rocking architecture can not only keep the displacement tends on a consistent level, but also consume rotational energy further through the sticky elastic damper on hinge point, reduce transient dynamic response of offshore platform structures effectively.5. Further proposed a new form of offshore platform- rocking column structure which based on TMD. It was analyzed and contracted with rocking column structure and MTMD applied on the offshore platform separately. The results showed that rocking column structure and MTMD can effectively reduce platform structure’s reaction power under different loads, but offshore platforms- rocking column structure which based on TMD and offshore platform is applied only to rocking column almost have same damping effect.6. For JZ20-2 platform structure, designed offshore platform test model structure based on rocking column according to the proportion of 1:10 scale. Designed suitable installation method and loads, do ice-induced pseudo-dynamic test. The test results further showed that the rocking column has a certain influence on improving the destruction of the platform structure, and has a nice vibration performance, enabling the displacements between the layers tend to be the same, has good inhibition effect on the dynamic response of the platform structure. |
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