Nanoscale mechanical properties and microstructure characterization of ultra-high performance fiber reinforced concrete materials

^1. Wuhan University of Engineering Science, Wuhan, 432700
^2. China University of Geosciences (Wuhan), Wuhan, 432700

Abstract

The construction of foundation engineering is developing towards high-rise and long-distance direction, and is facing more and more severe environmental threats. Traditional ordinary concrete materials have become increasingly difficult to meet these requirements. Ultra-high performance fiber concrete not only has higher mechanical properties than ordinary concrete, but also has better working performance and durability. Therefore, it can meet the requirements of high-rise, lightweight, intersection and longevity of building structures. The macro properties of materials obtained in different preparation processes are different. The microstructure research of materials links the preparation process with the macro properties from a scientific point of view. Fiber mixing improves the basic mechanical properties and impact fatigue performance of concrete, especially the effect of rigid fiber on improving the mechanical properties of concrete is significant. At the micro level, the fiber can inhibit the formation and development of microcracks. After the microcracks merge into macro cracks, the fibers restrict the crack development and increase the toughness and ductility.