MONITORING RC BRIDGE COLUMN HINGING WITH PHOTOGRAMMETRY

A simple photogrammetry method was used to investigate the displacements and rotations of points on column surfaces along the plastic hinging locations in a reinforced concrete bridge structure. Models that are created to represent the hinging behavior in reinforced concrete systems, and the resulting understanding of this behavior under different loading conditions, have traditionally been limited by the ability to validate the model with experimental data. For design and analysis methods leading to reliable performance-based engineering, a better model must be created to predict the extent and locations of nonlinear response in structural systems. As part of this effort, a model of hinging behavior in reinforced concrete bridge systems has been validated using photogrammetric data collected during the NEESR investigation of the seismic performance of four-span large-scale bridge systems at the University of Nevada Reno. The application of photogrammetric techniques in these structural tests used a reference grid on the column surface to record the movement of reference points during strong shaking. The advantages of the applied photogrammetry method are that it is inexpensive and simple to evaluate and can be accomplished remotely. The focus of this paper is the analysis of the photogrammetric data to compare surface deformations and rotations of a reinforced concrete bridge column subjected to dynamic excitation with the results from traditional instruments. The evaluation of the physical behavior of the reinforced concrete bridge column will be described elsewhere.