967265 Euler This research project is concerned with the development of new thin film strain gages. Three approaches will be used. The first employs wide band gap semiconductors as the active sensing element in a strain gage where both resistivity and absorption spectroscopy can be used to monitor the strain. These materials are attractive because they have good reproductivity, long term environmental and sensor stability, and large gage factors. The second approach will use polymers as the sensing element. The optical response of these materials is also sensitive to strain with the potential to lead to inexpensive, commodity level active strain elements. Finally, new polymers will be developed that store the integrated strain over time and can be used to measure accumulated damage to the substrate. The development of this aspect of the research relies on the ability to monitor the strain response conveniently such as during earthquake, wind, or vehicle induced structural vibrations using the optical methodology developed in the initial stages of the project. A successful outcome to the research will lead to cheaper strain gages that, because of the thin film nature, can be applied to buildings and infrastructure materials to monitor the strain and to assess the damage during a catastrophic event such as an earthquake. ***
