Development of Smart Braided Structures for Sensing of Geotechnical Structures

Abstract

This paper reports the development of innovative tri-axial braided structures for strain and damage sensing of geotechnical structures. These innovative braided structures have been developed through braiding of polyester multi-filaments over an axial core composed of mixture of conductive (carbon) and non-conductive (glass) fibres. It was observed that the developed structures were capable of self-monitoring of strain and damage and tailoring the composition of core fibres resulted in excellent sensing of low strain in continuous manner with gauge factor as high as 23. It was further observed that the mechanical performance and surface roughness (which controls their adhesion with soils) could be easily tailored through adjustment of core and sheath component's parameters, respectively. Furthermore, a self-sensing epoxy matrix containing uniformly distributed short carbon fibres was developed in order to combine with the developed braided structures (through impregnation using a special technique) and to further enhance their self-sensing capability. The results discussed in this paper depict that these tailorable and innovative braided structures can be advantageously applied in geotechnical structures for sensing purposes.