An Experimental Study of Temperature Effects on Modal Parameters of the Alamosa Canyon Bridge,
- H. Sohn, M. Dzwonczyk, E. G. Straser, A. S. Kiremidjian, K. H. Law, T. Meng
- Earthquake Engineering and Structural Dynamics,
This paper summarize a research effort towards the development of an integrated system for monitoring the condition of a civil structure, utilizing advanced sensing, microprocessing, wireless communication and damage diagnosis methods. Specifically, the discussions focus on the following issues: (1) the development of modular wireless vibration sensing, data acquisition and processing units; (2) the development of advanced structural damage assessment procedures; and (3) environmental effects on experimentally obtained modal parameters. Introduction The need for rapid assessment of the performance and safety of civil structures such as bridges, control centers, airports and hospitals, among many, has been amply demonstrated during recent natural disasters. In addition, continuous loading and extreme environmental conditions have caused extensive deterioration in our infrastructures. The ability to monitor the structural health of these systems is becoming increasingly important. The process of implementing a damage detection strategy is referred to as structural health monitoring. This process involves the observation of a structure over a period of time using periodically spaced measurements, the extraction of features from these measurements, and the analysis of these features to determine the current state of health of the system. For long term health monitoring, the task is to periodically update information regarding the ability of the structure to continue to perform its desired function. Under an extreme event, such as an earthquake, the objective is to provide in near real time reliable information about the safety of a structure and the performance level of the structure. The need for a systematic approach for “global” monitoring that can be applied to complex structures has led to the development of methods that examine changes in the vibration characteristics of a structure. Doebling et.al. provided a detailed literature review on many of the current (mostly deterministic) approaches for health monitoring of mechanical and structural systems . Housner et.al. summarized the current research and development specific to civil structures .