Arsava, K.S., Kim, Y., and Kim, K.H., 2016. Automatic control for hazard mitigation of coastal infrastructures. In: Vila-Concejo, A.; Bruce, E.; Kennedy, D.M., and McCarroll, R.J. (eds.), Proceedings of the 14th International Coastal Symposium (Sydney, Australia). Journal of Coastal Research, Special Issue, No. 75, pp. 1037 - 1041. Coconut Creek (Florida), ISSN 0749-0208.
This paper proposes to develop an acceleration feedback-based smart fuzzy controller for coastal bridge piers employing magnetorheological (MR) dampers. The proposed system reduces nonlinear structural responses to collision forces so that the risk of collapse is minimized. Based on the American Association of State Highway and Transportation Officials (AASHTO, 2012) specifications, a scaled coastal bridge pier was manufactured to mimic a full scale coastal bridge pier that has three columns and a pier cap. The scaled coastal bridge pier is equipped with an MR damper, accelerometers, an LVDT, strain gages, load cells, data acquisition systems, and a voltage-current converter. A variety of experimental studies were conducted on the smart coastal bridge pier under a variety of impact loads and control signals to generate sets of input data to train the proposed smart fuzzy controller. Passive and the proportional integral derivative controller (PID) were used as baselines. The performances of controllers were compared with those of the uncontrolled system in order to determine which system effectively reduces the collision responses of the coastal bridge pier. Comparisons of the smart fuzzy controller with the benchmark controllers demonstrated that the smart fuzzy controller is the most effective way to mitigate the structural collision response of integrated coastal bridge pier-MR damper systems subjected to various impact loadings.