Effectiveness of Retrofitting Damaged Concrete Beams with Sprayed Fiber-reinforced Polymer Coating

Abstract

An experimental investigation is conducted to evaluate the repair and strengthening performance of sprayed FRP coating on damaged plain and reinforced concrete beams. A series of flexure strength tests on damaged plain concrete beams repaired with sprayed FRP coating were carried out to evaluate the structural enhancement of the coating. The effects of parameters, such as coating thickness, fiber length, and fiber concentration, on the performance of repaired plain concrete beams were systematically investigated. The repair ability of the coating on precracked reinforced concrete beams was then quantified by comparing and contrasting it with other repair materials (e.g., fiber-reinforced mortar). The results, in conjunction with experimental observations reported in a preceding article, indicate that the sprayed FRP coating is capable of substantially increasing the strength as well as the ductility, and is effective in repair and strengthening of damaged concrete beams.

Keywords

sprayed FRP coating flexure strength test repair and strengthening of concrete fiber-reinforced mortar.

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