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A new strain transducer developed mainly for the inspection and evaluation of piping systems with excessive vibration is presented in this paper. Fatigue failure induced by vibration is one of the most common causes of piping failures. Procedures to evaluate the severity of piping vibration are usually based on pipe velocity or displacement. Although simple and fast, these procedures do not provide precise information on the risk of piping fatigue failure. Through the measurement of pipe dynamic strains the risk of failure due to vibration could be determined more accurately; however, the measurement of strain is usually performed using the conventional strain gage method, a time‐consuming technique that can be diffcult to implement in certain industrial scenarios. Motivated by the need of a simple and rapid method to measure pipe dynamic strains, a piezoelectric dynamic strain transducer has been developed. This work presents a description of the piezoelectric strain transducer and the preliminary results of pipe strain measurements. The transducer can be applied directly to the pipe through magnetic bases allowing for the quick measurement of dynamic strains in many points of the pipe. The transducer signal can be read with the same commercial data collectors used for accelerometers.

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This paper presents the results of an experimental investigation on the use of piezoelectric materials as a technique for monitoring the growth of defects in structures. The method consists of exciting the structure with piezoelectric actuators while recording the electromechanical responses from sensors placed close to the defect. The piezoelectric sensors detect the damage growth or an incipient defect by monitoring changes in the dynamic strain field, induced by the piezoelectric actuator, near the defect. This technique was evaluated through experiments using an aluminum frame structure. Results show that the piezoelectric active method is capable of detecting small changes in defect depth.