Stability control of a novel frame integrated with an SMA-MRF control system for marine structural applications based on the frequency analysis

Structural integrity and ensuring the stability of steel frame structures, including marine and coastal structures, are the main challenges for designers in civil infrastructures, particularly in oil platforms, subjected to tough periodic and non-periodic environmental loading conditions. Variable loadings with different amplitudes and frequencies may lead to the stability of steel structures loss. In order to keep the stability of the steel structures and prevent possible damages, reliable yet efficient structural control systems are in demand. Conventional structural control systems need significant activation energy and/or in-depth users knowledge to be effective. Most recently, smart materials and systems, notably shape memory alloy (SMA) and magnetorheological fluid (MRF), are considered to replace with the conventional systems. In this study, the SMA-MRF based structural control systems are installed in a simplified marine structure to investigate the frequency responses of the structure subjected to three scaled ground motions. Three structural parameters including the root-mean-square (RMS), the peak displacement, and particularly the frequency analysis are studied. The results show remarkable enhancement in structural behavior equipped with the SMA-MRF based system.