Flexural performance of bamboo fiber-reinforced concrete mixed with seawater and sea sand

In the face of the huge consumption of fresh water and river sand by the concrete industry and the poor flexural performance of plain concrete, it is theoretically feasible and environmentally friendly to use bamboo fiber as a replacement to reinforce concrete mixed with seawater and sea sand. In this research, taking the volume fraction (0.6%, 1.2%, and 2.4%), aspect ratio (10, 20, and 30) and diameter (1.0, 1.5, and 2.0 mm) of bamboo fibers as parameters, 15 groups of bamboo fiber-reinforced concrete (BFRC) prisms and one control group of plain seawater sea sand concrete prisms were subjected to four-point bending test, followed by analyzing the crack pattern, ultimate load, mid-span deflection and strain. Under the condition of 1.2% volume fraction, 20 aspect ratio, 1.5 mm diameter, and 30 mm length, the maximum increase rate of flexural strength in this research was obtained, and then it was compared with that of flexural strength of concrete prisms reinforced by various natural fibers. In addition, relevant fitting equations and theoretical calculation formulas were derived, laying a foundation for the subsequent research and application of BFRC.