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...
The underutilized tropical fruit tree, “cempedak” (Artocarpus integer (Thunb.) Merr. , Moraceae), is a major crop in Malaysia but the distribution of genetic diversity in the crop and its putative wild progenitor, “bangkong” (Artocarpus integer var. silvestris Corner), have not been studied. To investigate the diversity and origins of cempedak,...
Current ecological restoration efforts seek to restore a target community, maximize biodiversity or provide habitat for rare species. In practice, restoration ecology is often initiated and sustained without knowledge or reverence to the belowground ecosystem processes, though these processes often subtend the long-term sustainability of aboveground and belowground ecological communities.