There is an increasing use of Bonded Concrete overlay (BCO) in the repair or refurbishment of deteriorated concrete structures, and the addition of discrete fibers to the BCO improves its service life and reduces overlay thickness. Interface bond strength between the overlay and existing concrete is crucial for achieving the goal of concrete Structural rehabilitation. This work presents an experimental investigation of Splitting Tensile Bond Strength (STBS) and Direct Shear Bond Strength (DSBS) of BCO using two bond tests: a Splitting Tensile Bond Test (STBT) and Direct Shear Bond Test (DSBT). Four different types of synthetic discrete fiber and different fiber volume contents (0%, 0.5%, 0.8%, 1.0%, and 2.0%) were investigated, and seventeen different cases were prepared for each bond test. Results showed the interface bond strength to be significantly improved by the addition of synthetic discrete fibers compared to the concrete mix. In general, the addition of 1.0% of synthetic fibers to concrete led to an interface bond strength surpassing the minimum required. However, volume fraction dosage above 1.0% reduced the workability of the concrete mixture, leading to reduced bond strength.

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