Abstract: Strain in concrete is sensed by a helical optical fiber embedded in the concrete and connected at one end to an external light source, and at the other end to a light detector, providing a signal output to an information processor, which provides a display of the strain in the concrete.

Abstract: A system for monitoring strain in concrete structures comprises a frame for mbedding in the structure with first and second ends of the frame proximate an edge of the structure, a fiber-optic cable mounted on the frame and extending substantially from the frame first end to the frame second end, a light source in communication with a first end of the cable, a light detector in communication with a second end of the cable, and an information processor in communication with the light detector. The cable is adapted to propagate light from the source to the detector, and the processor is adapted to identify strain in the structure from data generated by the detector.