This Small business Innovation Research Phase I project investigates a method to monitor the mechanical response of civil engineering systems by use of fiber-optic sensors. The effect of forces exerted on structures during natural catastrophes -- such as earthquakes, hurricanes, tornadoes, floods, or severe storms could be measured. These devices will be rugged, low-cost, and will provide monitoring of strain in real time -- allowing a constant vigilance of the state-of-stress during aging and changing loading profiles. This would increase the ability of the engineer to assess the safety, state of repair, and expected lifetime of the structure. The ultimate goal of this research effort is to commercialize a fully developed optical sensor that can be used throughout the construction industry. The commercial sensor systems will contain "proven" low-cost optical-fibers, hardware, software, memory display, and support equipment. This will be achieved through research, and application of a new approach, that uses innovative ideas built on existing fiber-optic interferometric sensors. If successful, it will be possible to accurately measure the mechanical response properties of civil engineering structures in any desired location. Strain from long-term and transient loads can be measured and recorded. The sensors could be used in structures that use concrete such as buildings, parking garages, or bridges. Currently, large civil engineering structures are visually inspected. Extensometers or mechanical measuring devices are used on a periodic basis to evaluate the structure. Unfortunately, visual inspections usually occur after a structural problem has already manifested itself. Presently there are no sensing devices on the market that provide constant monitoring of the state of the structure.
