Fiber Reinforced Cementitious Matrix (FRCM) Composites for Reinforced Concrete Strengthening.

摘要

Fiber-reinforced composite systems are widely used for strengthening, repairing, and rehabilitation of reinforced concrete structural members. A promising newly-developed type of composite, comprised of fibers and an inorganic cement-based matrix, provides several environmental, structural, and sustainability-related advantages over fiber reinforced polymer (FRP) composites traditionally used in structural applications, which potentially expands the strengthening applications beyond those currently utilized. Such advantages include: 1) high resistance to fire and high temperatures; 2) resistance to UV radiation; 3) ease of handling during the application because the inorganic binder is water-based; 4) easy cleanup and reuse of tools; 5) low odor and toxin emissions during application and curing; 6) permeability compatibility with the concrete substrate; and 7) unvarying workability time (between 40DGF and 105DGF). Stress-transfer mechanisms and interfacial fracture propagation of fiber-reinforced composites externally-bonded to a concrete substrate are complex phenomena that are highly dependent on the bond characteristics of the composite matrix material to the fibers. These phenomena have not yet been clearly defined and understood for FRCM composites. Experimental work will be carried out in this study to isolate the shear debonding phenomenon using single lap shear tests.