Mitigation of Tsunami Debris Impact on Reinforced Concrete Buildings by Fender Structures

Buildings located in coastal regions are prone to tsunami dangers, which often carry debris in the form of shipping containers and boats. This paper presents an approach for the design of fender structures to minimize debris impacts on buildings. The impact of shipping containers, which are categorized as large debris, is considered in the study. Since the weights of shipping containers are standardized, the impact energy can be related to other debris. For a fender structure, cone-type rubber fenders are used to resist the impact of the shipping container. Various fender reactions are considered as parameters to study the efficiency of the fenders. The displacement-controlled nonlinear static analysis is carried out to determine the building capacity. The energy approach for shipping container impact is used to evaluate the resistance of the building. Capacity curves, energy absorptions, inter-story drift ratios of the buildings with and without a fender structure, and the efficiency of the fender are presented. The buildings with a fender structure can absorb the energy from the impact of a loaded shipping container. Conversely, the building without a fender structure cannot resist the impact of a loaded shipping container. From the obtained results, a recommendation is given for buildings with a fender structure. The hydrodynamic force on the fender structure is transferred to the main building through the fender. Hence, the yield force of the fenders affects the performance of the main building that must be considered in the design.