Temporal Evolution and 3d Locations of Acoustic Emis- Sions Produced from the Drying Shrinkage of Concrete
نویسندگان
چکیده
Acoustic emission activity produced by unrestrained drying shrinkage of an early age normal strength concrete specimen was measured with an array of fourteen broad-band high-fidelity acoustic emission sensors. The specimen was continuously monitored for 17 days, and full waveforms of the acoustic emissions were recorded throughout this time period. We present the source locations in three dimensions, the evolution of these events over time. Additionally, we discuss the reliability of source location estimates and consider uncertainty and bias introduced by array geometry effects, choice of velocity models, and poor picking of arrival times. We report on experimental procedures and tools created for fully quantitative, signal-based acoustic emission analysis.
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