Piezoresistive Properties of Smart Concrete Integrated with Nano Carbon Fibres

Research on multipurpose building materials has accelerated due to growing need for smart and sustainable infrastructure. Sustainable construction is not just about producing smart materials, also about minimising the construction and demolition waste caused by early structural breakdowns. This challenge is addressed by incorporating carbon fibre as a conductive filler in the concrete by enabling real-time monitoring of structures without relying on external sensors which allows timely maintenance of a structure. Developing a concrete composite that incorporates sensing features into structural elements extends the lifespan of structures reduces the demolition waste, allowing for real-time damage detection with carbon fibre as conductive filler of various proportions. This research investigates mechanical properties and electrical properties, optimised by the performance index which enhances compressive strength by 19.2%, split tensile strength by 46.12% and reduces the electrical resistivity by 57.4%. The stress, strain and formation of cracks are monitored in terms of change of resistivity and obtained the piezo resistivity with maximum fractional change in resistivity (FCR) as 61% and stress sensitivity as 1.53 % MPa−1. The microstructural characteristics of sensing concrete were also studied.