Concrete is the most widely used engineered material in the world and finds use in nearly every aspect of civil infrastructure. Safety concerns posed by the aging of infrastructure combined with the prevalence of concrete in these systems highlights the demand for a concrete-composite capable of structural health monitoring (SHM) while being low-cost and easily implementable. Embedment of electrically conductive forms of carbon such as graphitic fibers and nanotubes allow for concrete and other cementitious composites to act as self-sensors capable of SHM through a piezoresistivity mechanism. However, application of these composites is limited due to the high cost of carbon relative to concrete. Recently, the emergence of methane pyrolysis for hydrogen fuel production, which has a solid carbon byproduct, has shown to be a promising alternative to steam methane reforming, a primary byproduct of which being CO2. The scale up of methane pyrolysis may enable the application of self-sensing cementitious composites. This work looks to analyze the electrical, mechanical, and electromechanical effects of embedment of various forms and geometries of solid carbon in cement paste to form self-sensing cementitious composites. Our recent work has shown the mechanical properties of these composite materials are enhanced, especially in tension; and they exhibit strong piezoresistive response to applied load. Our work aims to optimize these properties. Further, the piezoelectric behavior of SSCCs will be explored towards the goal of being self-powered which will be valuable for broad implementation of these materials.
Project currently funded by: Federal