Identification of the stiffness distribution using BOTDR

BOTDR is one of the strain measurement technologies that is suitable for smart monitoring of civil engineering infrastructures. While the technology has the advantage of supplying spatially distributed data, it is currently limited to a spatial resolution of about 1 m. In a previous work, it was found that curvature increase along the beam can be related to the crack configuration. This, however, only appropriate to statically determinate beams, where no redistribution of internal forces is induced by the damage. Consequently, the use of the previously suggested relation to statically indeterminate beams may result in inaccurate estimation of the damage. In order to overcome this problem the current paper suggests an iterative identification algorithm which deals with statically indeterminate beams.