Defect Detection in Concrete Structures Using Homogeneous Length Sorted Single Walled Carbon NanoTube Sensors.

摘要

Material or geometrical property changes in the concrete results in the failure of the concrete structure. The detection of these uncontrolled failures in the early stages can prevent or eliminate catastrophic damage to the concrete structure. It has been shown that use of external piezo-electric and embedded sensors as foreign material involves more complexities in processing and is not cost effective. We present our research towards developing non-destructive diagnostic tools that will export information about the internal interactions of tailored cement nano-composites to data storage media. Single Walled Carbon Nanotubes (SWCNTs) in cement matrices can form useful nano-composite materials. This type of composite displays high tensile and flexural strengths, fracture toughness, low electrical resistivity, and high thermal conductivity. We investigate the use of homogeneous length sorted SWCNTs that are randomly distributed in percolated networks capable of being an internal responsive net mechanism. Our findings demonstrate increased microstructure sensitivity of our networks for our shorter length nanotubes near their critical percolation threshold. This shows promise for the development of even more sensitive, embedded piezoresistive SWCNT sensor for pre-emptive failure detection technology.;Key words: Carbon nanotubes, homogeneous length separation, SWCNT reinforced concrete, Crack detection, SWCNTs as sensors, Smart materials.