Multiscale, three-dimensional characterization of shock absorption in lightweight fibre reinforced cementitious systems

点击翻译按钮获取中文摘要

The development of protective systems depends not so much on superior strength alone, but on a combination of mechanisms which dissipate energy and absorb shock. Strategic inclusions such as lightweight solids and discrete reinforcement are known to fail locally and in the process, limit structural damage. Unfortunately, due to their heterogeneous nature and diversity in constituent properties, the tests that evaluate energy dispersion in these systems remain mostly macroscopic and the inherent disconnect between component scale has limited material modeling. The proposed research program will develop a multi-scale model to predict load rate effects in lightweight, fibre reinforced cementitious composites and specifically accomplish: i) 2-D and 3-D quantification of energy dissipating mechanisms in such systems; ii) experimental evaluation of their resilience descriptors at micro, meso and macro-scale; iii) predictive constitutive modeling of high strain rate sensitivity in such high performing systems. This proposal will integrate our understanding of dynamic crack growth and arrest process in cementitious materials that have proven high performance-to-weight ratio under standard tests. A combination of fracture tests and non-destructive techniques will be employed to quantify the volumetric response of cementitious composites to dynamic loading. The outcome is expected to inform on the rate sensitivity of heterogeneous brittle matrix systems in general and produce shock absorbing systems with multi-scale energy dissipation. Four graduate research assistants (1 PhD and 3 MSc) and 5 undergraduate students will join the research team. They will interact with research personnel in allied areas. Through the involvement of a diverse set of student researchers, a new generation of high quality personnel will be introduced to the use of high strain rate testing, non-destructive techniques, computational simulations and high performance structural materials.