In pursuit of bio-inspired triboluminescent multifunctional composites

Abstract

In the last three decades, much research work has gone into efforts to utilize the triboluminescence properties of some crystals for damage monitoring in engineering structures such as bridges and aircrafts. The key challenge from practical application point of view has to do with integrating the sensor in opaque composite structures and successfully transmitting and characterizing the TL signals generated due to damage in these structures. To solve this problem, we have developed the bio-inspired in-situ triboluminescent optical fiber (ITOF) sensor that mimics the sensory neurons of the human nervous system with an integrated sensing and transmission system. The integration of the TL-based sensing component and the transmission component has greatly enhanced the efficiency of side-coupling making distributed sensing along the entire coated length of the polymer optical fiber possible. Our group is the first to apply TL-based damage sensing to cementitious composite systems such as concrete structures to create multifunctional composites with both load carrying and in situ damage monitoring capabilities. This work will highlight key results and advances made in the development of cementitious as well as fiber reinforced polymer composites with in situ damage monitoring capabilities.