Calculation for Bearing Capacity of FRP-SSC Beams in Positive Section with Active CO2 Storage

With the comprehensive implementation of the China’s“Maritime Power”strategy, the utilization of FRP reinforced seawater-sea sand concrete (FRP-SSC) structures presents significant potential in alleviating the depletion of natural resources such as freshwater and river sand. The noteworthy advantage lies in its ability to locally sourced materials, thus offering substantial application prospects. Carbonation curing for FRP-reinforced seawater-sea sand concrete (FRP-SSC) structures on the other hand, can achieve highadded- value utilization and active storage of CO2, and reduce the adverse impact of the alkaline environment inside the SSC on the long-term durability of FRP bars. In this paper, it is proposed to divide the section of FRP-SSC beams into two kinds of concrete with different mechanical properties, carbonated and non-carbonated zones. According to the internal force balance and deformation coordination of the beam section, a calculation method for the flexural capacity of FRP-SSC beams with active CO2 storage is established. Finite element numerical model also is employed. Then, the influence law of carbonation depth on the flexural capacity of FRP-SSC beams is discussed. The results show that for FRP-SSC beams subjected to compression failure (more ideal mode of damage) , CO2 storage can increase the flexural capacity by 7. 75%. Considering that the flexural capacity in the ideal mode of damage is increased only by 16. 7% when the reinforcement ratio increases from 0. 74% to 1. 12%, CO2 storage shows a considerable improvement in the flexural capacity of FRP-SSC beams under certain circumstances. When FRP-SSC beams undergo tensile damage, CO2 storage has less effect on their flexural capacity.