Short-Term Strain Monitoring of Bridge Structures

Abstract

This report demonstrates how short-term field monitoring can be used to evaluate bridges when problems occur. A portable strain monitoring system with software has been used to study four different bridges. Studies to determine load-carrying capacities, causes of cracking, and load distributions are included. The work demonstrates that analytical predictions of stress/strain levels, load distributions, and fatigue estimations are conservative. Analytical models based on conservative assumptions are suitable for the design of new bridges, but when problems occur in existing bridges, field testing combined with careful analysis can provide much more accurate answers to assist engineers on proper courses of action for repair. The field monitoring reported in this study has resulted in substantial savings in the cost and time needed in renovation and/or repairs.