Impact of Polymer Coating on the Flexural Strength and Deflection Characteristics of Fiber-Reinforced Concrete Beams

Liquid polymers (LP) have become an important structural material used in the construction industry in the last decade. This paper investigates the viability of using commercially available LPs as a coating material to improve the flexural strength of fiber-modified concrete beams. The scope included preparing rectangular prism concrete beams with a concrete mixture including fly ash and fiber and coating them with four different liquid polymers at a uniform thickness following the curing process while one set of samples was maintained under the same conditions as a control group without coating. In addition, cylindrical samples were prepared to determine the compressive strength of the concrete mixture. Following the curing process in an unconfined open-air laboratory environment for another 28 days, concrete samples were tested to determine the flexural strength and deflection characteristics under center point loading equipment. The results revealed that all four coating types enhanced both the flexural strength and the average maximum deflection of the beams compared to the control group. While the enhancement in the flexural strength changed approximately between 5% and 36% depending on the coating type, the improvements in average maximum deflections varied between 3.7% and 28.4%.