Investigations on Pervious Concrete Properties Using Ultrasonic Wave Applications

The main objective of this study was to investigate the ultrasonic pulse velocity (UPV) in pervious concrete specimens, and then determine the tortuosity indices of those specimens using the airborne ultrasound method. Twenty-four pervious concrete mixtures were prepared and UPV was determined at four different gains. The experimental results indicated that, as gain increased, the UPV increased, and the rate of increase reduced at higher gains. Two statistical methods were utilized to investigate the effect of gain on UPV. An optimal gain was found from statistical assessment, which was rational in capturing correct UPV values of pervious concrete. The tortuosity experiments validated the existence of slow compressional waves, and indices determined in this study were in the range of 1.619–1.701. The scatter plots showed that with increase in porosity and permeability of pervious concrete mixture, there was a reduction in tortuosity. Additionally, tortuosity determined from airborne ultrasound technique agreed well with those estimated from available models.