R630A Rebar Scanner

Testing Quality of Concrete : Insitu Tests Using An Ultrasonic Pulse Velocity Tester(UPV Tester)

Ultrasonic pulse velocity tester or UPV as it is referred is one of the few methods utilised for in situ testing of quality of concrete and strength.As the name suggests, an ultrasonic pulse velocity tester is based on the principle of energized pulses generated and transmitted through a crystal transmitter of an ultrasonic transducer and received by a crystal receiver of an ultrasonic transducer. The frequencies utilized by industry recognized UPV concrete testers such as the Ultracon 170 from MKC Korea are generally commercially utilised low frequencies standardized at 54kHz.The time taken for the signal to be transmitted and received allows analysis of the quality of concrete. Test Method utilised for Insitu Ultrasonic pulse velocity testing of concrete: The UPV tester is utilised on a concrete structure greater than 30 cms in width. An ultrasonic couplant (gel/paste) is applied on the ultrasonic transducers to allow a strong contact between the transducers and the concrete to ensure a good signal transmission through the concrete. If both the transmitter and receiver transducers are applied in line with each other, the method is referred to as a direct method of concrete testing with an ultrasonic instrument. If the transmitter and receiver transducers are aligned perpendicular to each other, the method is referred to as an indirect method. Care must be taken to avoid rebar in the path of the ultrasonic waves to avoid influence from the same. Yardstick to be followed while interpreting results from a concrete ultrasonic pulse velocity tester : Pulse Velocity ft/sec Interpretation of measured values in relation to quality of concrete Above 15000 Excellent 12000 to 15000 Good 10000 to 12000 Questionable 7000 to 10000 Poor < 7000 Very Poor Application of UPV concrete testing in relation to building structures and building construction : Firstly, as suggested initially, the ultrasonic pulse velocity method is suggested as a standard method for establishing whether ...