This report shows the results of acoustic emission (AE) monitoring, and provides additional information on the nature of the ultrasonic indications in the north east trunnion shaft.
A remote global monitoring system is being operated on a 65 year old lift bridge in Sturgeon Bay Wisconsin. The system uses both strain gages and clinometers to continuously monitor the "health" of the fracture critical components of the bridge. Ruggedized miniaturized data loggers are locally mounted on the structure...
Current bridge condition determination is based almost entirely on the use of visual inspection. This approach to bridge inspection provides data that is subjective and not traceable. Nondestructive evaluation (NDE) is a tool that in actuality is little used on bridges, but could eliminate much of the subjectivity of the...
This technical report shows the findings of acoustic emission and strain gage monitoring tests conducted by research engineers of Infrastructure Technology Institute from Northwestern University on April 18, 1997 in Sacramento, California.
This report includes the findings of acoustic emission (AE) tests on the Fremont tied arch bridge in Portland Oregon conducted by research engineers from the Infrastructure Technology Institute of Northwestern University on March 24th, 1997.
This paper describes application of AE monitoring techniques to localize the sources of large noises in civil structures. These noises occur during operation of moveable portions of a structure in such things as lift bridges and moveable sports stadium roofs. The use of straightforward AE monitoring techniques can provide clear...
Kosnik, D. E., Northwestern University . Infrastructure Technology Institute, Department of Civil Environmental Engineering, Robert R. McCormick School of Engineering Applied Science. (2008). A new approach to acoustic emission testing of difficult-to-reach steel bridge details. Evanston, Illinois: Infrastructure Technology Institute/Department of Civil & Environmental Engineering.
Acoustic emission (AE) testing was used to identify the source of audible “bangs” generated during opening and closing of a large, double-leaf rolling-lift bascule bridge. The data were analyzed using a combination of well-established AE
techniques, including first hit analysis (FHA), planar location analysis, and linear location analysis. The FHA...
Scour is by far the primary cause of bridge failures in the United States. Scour and other hydraulic effects are particularly threatening because the deterioration is often invisible, hidden beneath turbid water. Many scour monitoring methods attempt to measure the development of scour pockets themselves. However, this is difficult due...
Acoustic emission (AE) testing was deployed on details of two large steel Interstate Highway bridges: one cantilever through-truss and one trapezoidal box girder bridge. Quantitative measurements of activity levels at known and suspected crack locations were made by monitoring AE under normal service loads (e.g., live traffic and wind). AE...