Assessment of the Compressive Strength of Self-Consolidating Concrete Subjected to Freeze-Thaw Cycles Using Ultrasonic Pulse Velocity Method

Abstract

Abstract: The development and use of self-consolidating concrete (SCC) considerably increased in the last decade. This work aims to evaluate the effect of using air-entraining admixture (AEA) on the compressive strength of SCC subjected to freeze–thaw (F–T) cycles. For comparison purposes, six mixtures were prepared with fixed powder content of 580 kg/m3 and sorted into two categories of unmodified and air-entrained SCC mixtures. For each category, the water-to-cement ratio (w/c) varied at 0.45, 0.5, and 0.56. The corresponding compressive strength and ultrasonic pulse velocity (UPV) measurements were carried out on samples before and after being subjected to 400 F–T cycles. Test results demonstrated that AEA enhanced the performance of SCC, particularly at lower rates of w/c. Air void characteristics records validate the enhanced performance for air-entrained SCC, given the air void system that accommodated the disruptive expansive stresses resulting from F–T cycles. Furthermore, the residual compressive strength of SCC can be accurately estimated by using UPV measurements.