IDENTIFYING DELAMINATION IN COMPOSITE BEAMS USING BUILT-IN PIEZOELECTRICS .1. EXPERIMENTS AND ANALYSIS

An investigation was performed on using piezoelectrics built into laminated composite structures to detect a delamination and estimate its size and location. Both experiments and analysis were conducted. In experiments, piezoceramics were attached to composite beams with and without an artificial delamination. Some of the piezoceramics were used as actuators to dynamically excite specimens while others were used as sensors to measure the beam responses. Tests showed that a delamination changed the measured piezo-induced dynamic forced response of beams. A delamination identification method is proposed which consists of a structural analysis, a response comparator, and a damage selector. The structural analysis was developed for predicting the output voltages of the sensors when a delaminated beam was excited by the actuators. The experimental results as well as the structural analysis are described in Part I of the study. In Part II, a response comparator and damage selector will be presented and will be integrated with the structural analysis for identifying delamination in composite beams with built-in piezoelectrics.