Page 11 - CBT 2018

Structural Health Monitoring of Infrastructure
The I-35W Saint Anthony Falls Bridge monitoring system contains over 500 sensors. The static system consists
of vibrating wire strain gages and thermistors. The dynamic system consists of linear potentiometers at the bearings, resistive strain gages, and accelerometers predominantly in the southbound river span. This structural health monitoring system, alongside routine inspection, offers a unique test-bed to develop efficient strategies to identify information regarding structural changes in the presence of environmental loading. The efficient application of output-only system identification techniques demonstrates the viability of using accelerometer measurements for long term monitoring of the structure and highlights the significant impact that temperature
and humidity have on the dynamic signature of the structure. Systems such as this can play a critical role toward development of decision-making tools to best utilize limited resources for infrastructure investment. [7,8]
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