Abstract

Aging and deterioration of existing structures and the need for rapid assessment and evaluation of these structures for hazard mitigation have significantly expanded the research efforts in the field of structural health monitoring (SHM). SHM involves monitoring of a structure using periodically sampled measurements, extraction of damage sensitive features from these measurements, and assessment of the current health state/integrity of the system. Extraction of damage signatures that allows one to distinguish between the undamaged and the damaged structure from the measured vibration response is the area of SHM that receives the most attention. This paper presents a critical review of the damage assessment methodologies based on the research and applications reported in the literature. Challenges and research gaps in SHM are emphasized. These challenges include optimization of the number and location of sensors, identification of features sensitive to small damage levels, ability to discriminate changes in these features caused by damage from those caused by changing environmental or test conditions, and development of statistical methods to discriminate features from structures in undamaged and damaged states. A companion paper presents an application on the vibration data obtained from the ASCE benchmark structure.

Key words: Vibration based structural health monitoring, global methods, damage assessment.