Experimental Investigation of Ultrasonic Pulse Velocity (UPV) Test Specimen in Assessing the Strength of Steel Fiber Reinforced Concrete Structure

Abstract

This study aims to conduct the Ultrasonic Pulse Velocity (UPV) test and compressive strength test of Steel Fiber Reinforced Concrete (SFRC). This paper also examines the correlation of UPV test data and compressive strength test data for SFRC specimens. The experiments were carried out with the same value of the water-cement ratio, superplasticizer but different fiber volumes of steel fiber. Twelve prism sizes 100mm x 100mm x 500mm were casted and 0.5%, 1.0%, and 1.5% of steel fiber reinforced concrete were added and the prisms undergone curing for 7, 14 and 28 days. The highest value of the UPV test at the x-axis is SFRC-0.5%, 6.26 km/s at seven days and 6.8377 km/s at 14 days. The highest value of the UPV test at the y-axis is SFR-0.5%, 6.68 km/s at seven days and 6.34 km/s at 28 days. Nevertheless, the grading is still considered excellent concrete quality based on BS1881. The highest value of compressive strength is SFRC-1.0%, 193.2 MPa at 14 days. The R-squared value for the correlation coefficient between UPV result and the compressive strength result at the x-axis and y-axis is 0.9963 and 0.9966 respectively. The non-linear models show high regression coefficient of R-squared close to 1.00, which means the parameters are strongly correlated. The correlation equation obtained can be used to predict compressive strength based on UPV data for steel fiber volume fraction up to 1.5%. Thus, it can be concluded that percentage of steel fiber added, affect the strength of the tested concrete specimens and the optimized value of steel fiber added is at 1% in this study.

The Effect of Polypropylene Fiber Addition on the Compressive Strength and Ultrasonic Pulse Velocity of Low-Temperature Cured AlkaliActivated Slag

“…The introduction of fibers into the material can alter its acoustic properties by affecting the path of the ultrasonic waves. The presence of fibers may scatter or attenuate the ultrasonic pulses to a certain degree, leading to lower UPV values [34,35]. The increase in the 7-day UPV value from 2717 m/s to 2898 m/s with an increase in Na2O% from 7% to 9% indicates that higher alkali dosages have a positive effect on the ultrasonic properties of the AAS during early stages of curing.…”