Dynamic Monitoring of Steel Girder Highway Bridge

Longterm sensor-based monitoring of an LRFD designed steel girder bridge

“…The effect of end bearings constrains on the development of internal stresses in continuous steel girders has been overlooked in the literature and design procedures. Zhao and De Wolf [41] applied dynamic testing techniques to identify the overall changes in the structural behavior of a bridge and concluded that partial restrains in end bearings accounted for a change in the natural frequency of 15.4%. In this study, the partial movement restrains recorded at Abutment 1 explains the large axial forces developed at the steel girders, as shown in Fig.…”

NDT Monitoring of Bridges using Innovative High Precision Surveying System

“…During the past decade many research studies have focused on the possibility of using structural vibration characteristics to evaluate structural health or to assess its performance under severe excitation. Although the use of dynamic properties has advantages over the use of static ones (Zhao and DeWolf 2002), it is not so easy to excite a large scale structure in order to monitor its dynamic performance. In the particular case of bridges of small and large scale, daily traffic is only able to excite lower natural frequencies and mode shapes.…”

A Transducer for Measuring Tensile Strains in Concrete Bridge Girders

“…Laser [3] and photogrammetric [4] devices measure vertical deflections and do not require anchorage to the ground, an advantage when the bridge section measured is over water or traffic. Some researchers have measured the dynamic response of a bridge [5,6] for the purpose of detecting damage or deterioration (indicated by a change in dynamic response. )…”