导管架式海洋平台结构的磁流变阻尼隔震控制

Smart Isolation Systems of Offshore Platform Jacket Structure with Magnetorheological Dampers

首先针对渤海JZ20-2MUQ导管架式海洋平台结构,建立了应用磁流变阻尼器的智能隔震体系,并通过对导管架式海洋平台结构特点和磁流变阻尼器性能的分析,提出了磁流变限位型阻尼器被动控制、Passive off、Passive on和半主动四种控制方案。然后,分别在冰激振动和地震作用下,对平台隔震结构进行了数值仿真计算,分析比较了不同磁流变阻尼控制方案对平台隔震结构的控制效果以及对隔震层变形的限制作用。结果表明。磁流变阻尼隔震控制方案能有效控制导管架式平台结构的振动,平台结构位移和甲板加速度反应可降低30％以上,隔震层变形可控制在40mm左右的有限范围内。

A smart isolation system with magnetorheological dampers is put forward for offshore platform jacket structures such as JZ20-2MUQ platform in Bohai Ocean, which consists of the isolators and magnetorheological dampers installed on the kyer between the jacket structure and the upper deck. First of all, taking full account of the characteristics of offshore platform jacket structures and also the objectives to be reached for the control system, such as suppressing the displacement of jacket structure and the acceleration of deck as well as limiting the relative displacement of isolated layer, several kinds of control schemes including displacement-limited passive, passive-off, passive-on and semi-active control are suggested and studied for the system. And then under ice-induced vibration and seismic excitation, the responses of the system are simulated to evaluate the control effects of MR dampers on the superstructure and isolated layer. All simulation results show that MR dampers are rather efficient devices to reduce the displacement of jacket structure and acceleration of deck up to 30 % , and the drift isolated layer can be controlled in about 40mm.