Abstract: A non-intrusive monitoring method and system for the detection and potential assessment of damage that may occur during a manufacturing process is described. Potential damage events such as impact events can be detected by one or more sensors located on a workpiece or on a machine utilized in the manufacturing process. Through wireless monitoring of the sensors, potential damage events are detected and products of the manufacturing process can be examined to determine if the event has led to damage.

Abstract: Fly ash-based geopolymer binders and activating solutions for use in forming a concrete as well as methods for forming concrete including the binders are described. The fly ash-based geopolymer binders include a combination of fly ash, silica fume, and sodium hydroxide as well as an amount of Portland cement. Concretes formed of the binders can exhibit excellent compressive strength and fuel energy characteristics as well as being more cost efficient as compared to other concretes. The inclusion of an amount of Portland cement in the binders can allow for a decrease in sodium hydroxide and silica fume content while maintaining desirable compressive strength characteristics.

Abstract: Fly ash-based geopolymer binders and activating solutions for use in forming a concrete as well as methods for forming concrete including the binders are described. The fly ash-based geopolymer binders include a combination of fly ash, silica fume, and sodium hydroxide as well as an amount of Portland cement. Concretes formed of the binders can exhibit excellent compressive strength and fuel energy characteristics as well as being more cost efficient as compared to other concretes. The inclusion of an amount of Portland cement in the binders can allow for a decrease in sodium hydroxide and silica fume content while maintaining desirable compressive strength characteristics.

Abstract: Methods of using acoustic emission (AE) as a condition assessment technique for alkali-silica reaction (ASR) in concrete are provided. ASR is a chemical reaction occurring between alkaline hydroxides within cement past and certain types of amorphous silica found in mineral aggregates. ASR causes an accumulation of internal pressure due to the formation of a hygroscopic gel which leads to expansion and cracking of the concrete. AE is highly sensitive to stress waves emitted from a sudden release of energy such as formation of cracks in concrete. This allows it to capture and identify propagating damage. AE has the potential to detect micro-cracks forming prior to expansion, which can be related to the degree of ASR damage.

Abstract: A non-intrusive monitoring method and system for the detection and potential assessment of damage that may occur during a manufacturing process is described. Potential damage events such as impact events can be detected by one or more sensors located on a workpiece or on a machine utilized in the manufacturing process. Through wireless monitoring of the sensors, potential damage events are detected and products of the manufacturing process can be examined to determine if the event has led to damage.

Abstract: Methods of using acoustic emission (AE) as a condition assessment technique for alkali-silica reaction (ASR) in concrete are provided. ASR is a chemical reaction occurring between alkaline hydroxides within cement past and certain types of amorphous silica found in mineral aggregates. ASR causes an accumulation of internal pressure due to the formation of a hygroscopic gel which leads to expansion and cracking of the concrete. AE is highly sensitive to stress waves emitted from a sudden release of energy such as formation of cracks in concrete. This allows it to capture and identify propagating damage. AE has the potential to detect micro-cracks forming prior to expansion, which can be related to the degree of ASR damage.

Abstract: Methods are provided for detecting damage in a post-tensioned concrete specimen due to corrosion. In one embodiment, the method comprises mounting at least two piezoelectric sensors onto the surface of the post-tensioned concrete specimen; receiving acoustic emission signals at the piezoelectric sensors; recording the acoustic emission signals with associated parameters and waveforms; and filtering the data for example using Root Mean Square data and the average frequency data.