ABSTRACT
In structural health monitoring (SHM) of civil infrastructure, vibration-based techniques are being popularly employed. The vibration signatures carry useful information such as structure’s dynamics and the state of the structure, which are normally extracted through modal- or non-modal-based techniques. In SHM, it is extremely important to detect subtle damages (small cracks) present in the structure at their incipient state. Also, environmental variability (EOV) is another factor that needs to be addressed while employing SHM. However, these are still the biggest challenges for SHM community. In this chapter, multi-model-based damage diagnostic techniques to detect the minor incipient cracks through signal decomposition and reconstruction are presented. An efficient technique to handle EOV is also presented. Experimental investigation results are presented to demonstrate the practical applicability of the proposed techniques. Also, recently, indirect SHM using vehicle scanning approach is getting importance as it possesses various advantages such as non-requirement of sensor installation on the structure, traffic closure, and maintenance of sensor systems. A modal identification technique using indirect SHM for bridges is also presented.
