Real-time fast ultrasonic monitoring of concrete cracking using embedded piezoelectric transducers

Abstract

This paper deals with the use of embedded piezoelectric transducers for ultrasonic monitoring of cracking in concrete. Based on the previous developments of our research team on that topic, we design a new data acquisition system which is able to interrogate the emitter-receiver pair up to 150 times per second. The system is based on low-voltage actuation (up to 20 Volts) and the signal-to-noise ratio is excellent due to the use of a voltage amplifier at the receiver side and the possibility to perform averages. With such a high measurement rate, we are able to follow brittle failure events such as the failure of a concrete cylinder in compression, which is the application example presented. In this application, we show that, in addition to the ultrasonic active monitoring of cracking, the system is also able to record the passive acoustic emission events which can be used as a complementary indicator of damage in the cylinder. We also demonstrate that because of the high level of stresses in compression, the damage indicator defined in our previous studies is not suited for crack monitoring due to the elastoacoustic effect. The amplitude of the first wave arrival is shown to be a robust alternative damage indicator allowing to follow accurately the three successive phases of cracking leading to the failure of the cylinder.

Ultrasonic Monitoring of Crack Propagation of Notched Concretes Using Embedded Piezo-electric Transducers

“…In this investigation, ultrasonic damage index based on the variation of amplitude of receiving signal in the time window of the first half-period is chosen as an indicator to evaluate the damage of notched concrete. It should be noted that the first period of receiving signal accords with the shortest wave path, which is only influenced by the mechanical properties of concrete between emitter and receiver (Dumoulin and Deraemaeker 2017b;Dumoulin et al 2014). The damage index which is similar to the estimation of the corrosion variation of reinforcing bar in concrete (Du et al 2017), can be written as,…”

“…Acoustic emission (AE) technique has overwhelming advantages in detecting crack initiation, location and propagation over conventional methods based on the recording of transient signals, which correspond to newly initiated cracks or even propagation of existing cracks (Pei et al 2015;Zhang et al 2016). Dumoulin and Deraemaeker (2017b) pointed out that information may be lost and cannot be recovered if the AE monitoring system does not run during the cracking process in comparison with ultrasonic method. Therefore, the choice of defects identification in concrete between AE technique and ultrasonic method depends on instrument capability, serviceable range, condition and actual need.…”

Detecting of the Longitudinal Grouting Quality in Prestressed Curved Tendon Duct Using Piezoceramic Transducers

“…In recent years, piezoceramics transducers have been used to monitor structural health [28][29][30]. Piezoceramic transducers have their superiorities of wide frequency range [31][32][33], low cost [34,35], energy harvesting [36][37][38], and the dual functions as a sensor and an actuator.…”

Embedding ultrasonic transducers in concrete: A lifelong monitoring technology

“…Such kinds of transducers have been successfully used for the monitoring of (i) cement and concrete hydration [14,15], (ii) the evolution of the compressive strength of concrete at early age [16,17], (iii) concrete cracking [18][19][20][21][22], (iv) water seepage [23][24][25] and (v) mechanical properties of concrete [26] including the acoustoelastic effect in compression [27]. At ULB-BATir, we have worked on the development of our own embedded transducers to measure the P-wave velocity at early-age [28] and monitor cracking in several laboratory tests [29,30] (pull-out, three-points bending and compressive tests).…”