Characterization of Ultra-High Performance Concrete for Impact Resistant Structures

Ultra-high performance concrete (UHPC) is a dual use technology---it has both civilian and military application. The material is characterized by a very high compressive strength coupled with high energy dissipation from fiber reinforcement, and is sought after for use in structures subject to dynamic loading. The high incidence of structural dynamic loading requires advanced damage suppression techniques. This thesis reports on a combination of numerical and experimental techniques to facilitate the development of UHPC for impact resistant structural application. The Lattice Discrete Particle Model is utilized to simulate impact loading. The model captures the change in material properties, and the intrinsic and apparent fracture and fragmentation effects under high-strain rates essential for impact studies. Finally, a tensile test method is proposed to investigate the micro-mechanics of hooked fiber reinforcement in UHPC, and produce computational targeted experimental data for accurate modeling of the pull-out process used to characterize the fiber-matrix concrete interface.