DURABILITY OF ZNS: MN TRIBOLUMINESCENT SENSOR FOR IMPACT DAMAGE MONITORING IN CIVIL INFRASTRUCTURE

摘要

The United States' critical civil infrastructure systems (CIS) such as bridges, dams and tunnels are aging and overloaded, thereby exposing millions of users to danger daily. While over 50% of the nearly 600,000 US bridges are more than 60 years old, the average daily vehicular crossings is about 4 billion vehicles. Adding to the risks commuters are exposed to is the effect of vehicular impacts these structures are continually being subjected to. Bridge overload and lateral impact forces from trucks, barges/ships, and trains were responsible for 20% of total bridge failures. By utilizing the triboluminescent (TL) property of ZnS:Mn, our group has developed the in-situ triboluminescent optical fiber (ITOF) sensor that will enable real time and distributed impact damage monitoring of the CIS. The sensor consists of ZnS:Mn and UV-cured acrylated urethane composite coating on polymer optical fiber. The durability of the ITOF sensor under repeated impact loading is however critical for its effective deployment in CIS. The durability of the triboluminescent material under different impact load levels will be investigated. The repeatability and degradation of the triboluminescent responses of the sensor under many cycles of impact loading will be reported. Optical and scanning electron microscopes will be employed to characterize the level of damage of the sensor after the impact events.