Ultra high performance fiber reinforced concrete and method for manufacturing the same

Abstract

This invention discloses an ultra-high performance fiber-reinforced concrete and its preparation method, belonging to the field of concrete technology. By acid etching of high-silica glass fibers with sulfuric acid and nitric acid, the surface roughness of the fibers is increased, and a large number of active groups such as hydroxyl groups are introduced, providing reaction sites for subsequent dopamine grafting. This solves the problems of strong surface inertness and weak interfacial bonding between glass fibers and the concrete matrix. Compared with traditional concrete, the internal structure is highly dense, with high compressive strength and is not easily corroded by alkaline media. Furthermore, this invention forms a highly active adhesive coating on the fiber surface by covalently bonding the catechol groups of dopamine with the hydroxyl groups on the fiber surface. Simultaneously, the amino and phenolic hydroxyl groups of the dopamine coating act as bridges, enhancing the bonding force between the fiber and subsequent silanes and bentonite, significantly improving the interfacial compatibility between the fiber and the concrete matrix, and reducing the risk of interfacial debonding under stress.