2007 年 10 巻 p. 983-994
RC structural health monitoring (SHM) often includes two main concerns on local damage detection and global structural behavior. In our recent study, a novel packaged long-gage fiber Bragg grating (FBG) sensor for practical adaptation in civil SHM has been developed and verified to have the ability to obtain effective macro-strain distributions. This paper is dedicated to proposing an integrated SHM strategy for RC flexural structures by employing the developed sensors. Experimental investigations on a normal RC beam installed with the FBG sensors of different gauge length are first carried out. On one hand, the ability of distributed FBG sensors to detect the occurrence, location and extent of cracks has been testified in contrast with the results from foil strain gauges and crack gauges. On the other hand, a perfect linear correlation between the measurements from FBG sensors and those from displacement transducers has testified the sound performance of the developed sensors for global structural behavior evaluation. Numerical simulations based on section fiber modeling method with the plane section assumption are then performed to compare with the experimental results. Their nice agreements have further verified the ability of the FBG sensors to estimate structural parameters and evaluate structural global behavior. Regarding these meaningful investigations, the inverse analysis including load and structural parametric identification is carried out by utilizing the measured macro-strain distribution. An integrated SHM strategy based on distributed long-gage FBG sensors for RC flexural structures including local crack monitoring, parametric estimation and global behavior evaluation is proposed finally.
