Non-destructive Evaluation of the Properties of Self-compacting Concrete Using Ultrasonic Testing and a Rebound Hammer

Abstract

This study aims to improve the estimation of concrete compressive strength by combining destructive and non-destructive testing (ultrasound and sclerometer) to obtain a more precise and reliable assessment for quality control and the diagnosis of concrete structures. The experimental data were analyzed using a program linked to the Pundit Lab measurement tool to establish a regression model linking the ultrasonic propagation velocity (UPV) to the compressive strength of self-compacting concrete (SCC). SCC was formulated using a standard mix design with 450 kg/m³ of cement, 10% limestone filler (45 kg/m³), a water/cement ratio of 0.44, a gravel/sand ratio of 1.0, and a polycarboxylate-based superplasticizer. The fresh properties were evaluated using cone slump tests, L-box tests, V-funnel tests, and sieve stability tests, confirming the self-compacting nature of the mix. After 28 days of curing, five cylindrical specimens (160 × 320 mm) were subjected to ultrasonic (UPV), sclerometric, and compression tests. The results showed an average compressive strength of 39.06 MPa, a modulus of elasticity of 41.5 GPa, and a shear modulus of 16.7 GPa. The developed regression model improved the accuracy of compressive strength estimation by combining ultrasonic and sclerometric measurements, thus providing a reliable method for quality control and evaluation of existing concrete structures.