Inadequate vertical clearance is listed as a leading cause of accidents involving highway bridges in many States. In addition, state bridge engineers list over-height loads as the leading cause of damages to pre-stressed concrete bridges. As rampant and destructive as over-height vehicle collisions are, there is no technology in use for monitoring vehicle collisions on our bridges. In fact, very few states collect data on bridge hits. Very significant maintenance budget savings can be achieved if over-height vehicle collisions can be prevented with an effective monitoring system.
In this proposal, the team has developed the In-situ Triboluminescent Optical Fiber (ITOF) sensor. This proposed technology is an integrated sensing and signal transmission sensor system that can function as a triboluminescent optical nerve analogous to the nerves in mammals. The ITOF system may be readily integrated into large civil and aerospace structures to provide in-situ, distributed and real time damage monitoring. The ITOF sensor combines the highly desirable features of polymer optical fibers (POF) such as lightweight, smaller sizes, immunity to electromagnetic interference and capacity for distributed sensing with the triboluminescent (TL) property of ZnS:Mn. The ITOF sensor has an integrated sensing (triboluminescence sensory receptor) and transmission component (polymer optical fiber) that converts the energy from damage events like impacts and crack propagation into optical signals that are indicative of the magnitude of damage in composite structures.
