Nanostructure of Cement/Polymer Fiber Interfaces

Concrete is the most used materials in the world. It is also one of the most versatile while complex materials which human have used for construction. However, concrete is weak in tension. Therefore, over the past thirty years many studies were focused to improve the tensile properties of concrete (cement-based composites) using a variety of physical and chemical methods. One of the most successful attempts is to use polymer fibers in the structure of concrete to obtain a composite with high tensile strength and ductility. However, a thorough understanding of the mechanical behavior of fiber reinforced concrete requires the knowledge of fiber/matrix interfaces at the small scale. In this study, experimental techniques have been used to study the nanostructure of fiber/matrix interfaces. Based on Scanning Electron Microscopy (SEM) and Energy-dispersive X-ray spectroscopy (EDX) analysis, the calcium-silicate-hydrate (C-S-H)/fiber interfaces of two different polymer fibers, polyvinyl alcohol and polypropylene, was numerically studied at the atomistic level.