An Experimental Study on Static and Dynamic Strain Sensitivity of Embeddable Smart Concrete Sensors Doped with Carbon Nanotubes for SHM of Large Structures

The availability of new self-sensing cement-based strain sensors allows the development of dense sensor networks for Structural Health Monitoring (SHM) of reinforced concrete structures. These sensors are fabricated by doping cement-matrix materials with conductive fillers, such as Multi Walled Carbon Nanotubes (MWCNTs), and can be embedded into structural elements made of reinforced concrete prior to casting. The strain sensing principle is based on the multifunctional composites outputting a measurable change in their electrical properties when subjected to a deformation. Previous work by the authors was devoted to material fabrication, modeling and applications in SHM. In this paper, we investigate the behavior of several sensors fabricated with and without aggregates and with different MWCNTs content. The strain sensitivity of the sensors, in terms of fractional change in electrical resistivity for unit strain, as well as their linearity are investigated through experimental testing under both static and dynamically varying compressive loadings. Moreover, the responses of the sensors when subjected to destructive compressive tests are evaluated. Overall, the presented results contribute to improving the scientific knowledge on the behavior of smart concrete sensors and to furthering their understanding for SHM applications.

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Complex Geometry Strain Sensors Based on 3D Printed Nanocomposites: Spring, Three-Column Device and Footstep-Sensing Platform

Nanomaterials ◽

10.3390/nano11051106 ◽

2021 ◽

Vol 11 (5) ◽

pp. 1106

Author(s):

Alejandro Cortés ◽

Xoan F. Sánchez-Romate ◽

Alberto Jiménez-Suárez ◽

Mónica Campo ◽

Ali Esmaeili ◽

...

Keyword(s):

Carbon Nanotubes ◽

3D Printing ◽

Complex Geometry ◽

Uv Light ◽

Shielding Effect ◽

Strain Sensitivity ◽

Printing Technology ◽

3D Printing Technology ◽

Sensing Platform ◽

Electromechanical Performance

Electromechanical sensing devices, based on resins doped with carbon nanotubes, were developed by digital light processing (DLP) 3D printing technology in order to increase design freedom and identify new future and innovative applications. The analysis of electromechanical properties was carried out on specific sensors manufactured by DLP 3D printing technology with complex geometries: a spring, a three-column device and a footstep-sensing platform based on the three-column device. All of them show a great sensitivity of the measured electrical resistance to the applied load and high cyclic reproducibility, demonstrating their versatility and applicability to be implemented in numerous items in our daily lives or in industrial devices. Different types of carbon nanotubes—single-walled, double-walled and multi-walled CNTs (SWCNTs, DWCNTs, MWCNTs)—were used to evaluate the effect of their morphology on electrical and electromechanical performance. SWCNT- and DWCNT-doped nanocomposites presented a higher Tg compared with MWCNT-doped nanocomposites due to a lower UV light shielding effect. This phenomenon also justifies the decrease of nanocomposite Tg with the increase of CNT content in every case. The electromechanical analysis reveals that SWCNT- and DWCNT-doped nanocomposites show a higher electromechanical performance than nanocomposites doped with MWCNTs, with a slight increment of strain sensitivity in tensile conditions, but also a significant strain sensitivity gain at bending conditions.

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An Experimental Study on Addition of Carbon Nanotubes to Improve the Performance of UHPC

Lecture Notes in Civil Engineering - Proceedings of SECON'19 ◽

10.1007/978-3-030-26365-2_74 ◽

2019 ◽

pp. 811-817

Author(s):

A. Aayisha ◽

Regi P. Mohan

Keyword(s):

Carbon Nanotubes ◽

Experimental Study

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Closing in on the Neural Mechanisms of Finger Joint Angle Sense. Focus on “Quantitative Analysis of Dynamic Strain Sensitivity in Human Skin Mechanoreceptors”

Journal of Neurophysiology ◽

10.1152/jn.00724.2004 ◽

2004 ◽

Vol 92 (6) ◽

pp. 3167-3168 ◽

Cited By ~ 8

Author(s):

Kenneth Johnson

Keyword(s):

Quantitative Analysis ◽

Human Skin ◽

Joint Angle ◽

Neural Mechanisms ◽

Finger Joint ◽

Dynamic Strain ◽

Strain Sensitivity ◽

Skin Mechanoreceptors

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Biological activity of carbon nanoparticles produced in combustion process

Combustion Engines ◽

10.19206/ce-2019-445 ◽

2019 ◽

Vol 179 (4) ◽

pp. 269-273

Author(s):

Jarosław KAŁUŻNY ◽

Natalia IDASZEWSKA ◽

Tomasz RUNKA ◽

Adam PIASECKI ◽

Marek NOWICKI ◽

...

Keyword(s):

Carbon Nanotubes ◽

Experimental Study ◽

Carbon Nanoparticles ◽

Dominant Role ◽

Combustion Process ◽

Industrial Applications ◽

Carbon Allotropes ◽

Air Purifier ◽

Residential Space

In the recent years industrial applications of carbon allotropes such as carbon nanotubes (CNTs) and graphene have been tested extensively, thus justifying research on the environmental impact these materials have. In the current paper we compare EDS spectroscopy results of a cabin filter used in a car to a filter used in an air purifier inside a residential space. The contaminants adsorbed on the carbon nanoparticles trapped in both types of filters allows for determining of their source of origin demonstrating clearly the dominant role of non-road emissions in Poland. Finally we present the experimental study on the growth of plants on substrates intentionally enriched with CNTs.

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