To reinforce elevated bridge beams and floor blocks and building pillars and walls, as well as general structures, in high durability, by covering structural members with a specific aramid fiber sheet followed by impregnating the sheet with an ultraviolet light stabilizer-contg. adhesive to effect bonding.

Reinforcing aramid fibers 1, 1', 1"... are unidirectionally or in a two-way fashion, longitudinally and transversely, arranged spacedly in rows, covering auxiliary fibers 3, 4 crossing with the respective groups of the reinforcing fibers are then disposed in the longitudinal direction of these reinforcing fibers, and the groups of the reinforcing fibers are mutually bound in an interrow fashion in warp knit texture through entangling auxiliary fibers 6. Next, the reinforcing aramid fiber sheet is laid, via an adhesive, along the circumferential direction and/or longitudinal direction of structural members, and at least the outermost layer portion of the resultant covering fibrous sheet is impregnated with an ultraviolet light stabilizer-contg. adhesive to effect bonding.