Many maritime structures (e.g., locks, dams, ports) in the US are either reaching or are past their design lives, and there are limited funds for the necessary maintenance activities which can lead to repairs that requires closures. These structures are not easy to detour and often require dewatering before repairs can be made, closures can cause delays and business-related losses which can have a large effect on the nation’s economy. Thus, it is advantageous to reduce the repair time for maritime structures. BCSA (belitic calcium sulfoaluminate) cement is a promising material to perform this type of repair due to its properties. BCSA cement is a fast-setting hydraulic cement capable of reaching compressive strengths greater than 4000 psi (27.6 MPa) in less than 2 hours. BCSA also has low shrinkage and good long-term strengths. This research consisted of developing an optimal rapid-setting underwater mortar mixture design using BCSA cement. Properties such as compressive strength and workability were tested to choose the best mix design. Additionally, soil cements made with BCSA cement were compared to portland cement-based soil cements. These soil cements have applications for rapid repair of levees and earthen dams, but also for rapid soil stabilization. The results obtained prove that BCSA cement is feasible to rapidly perform underwater repairs and repairs of soil-based waterway structures. Keywords: BCSA, underwater, repair, rapid-strength development, soil-cement
