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

轻质纤维增强水泥体系减震的多尺度、三维表征

• 批准号: 326880-2011
• 负责人: Bindiganavile, Vivek
• 金额: $ 1.46万
• 依托单位: University of Alberta
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2015
• 资助国家: 加拿大
• 起止时间: 2015-01-01 至 2016-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=571862
• 关键词: Multiscale; three; dimensional; characterization; shock

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.

保护系统的发展不仅依赖于超强的强度，还依赖于耗散能量和吸收冲击的多种机制的组合。已知轻质固体和离散加固等战略性内含物会在局部失效，并在此过程中限制结构损坏。不幸的是，由于它们的异质性和组成特性的多样性，评估这些系统中能量分散的测试仍然主要是宏观的，并且组件规模之间固有的脱节限制了材料建模。拟议的研究计划将开发一个多尺度模型来预测轻质纤维增强胶凝复合材料的载荷率效应，并具体完成：i)此类系统中能量耗散机制的二维和三维量化；Ii)在微观、中观和宏观尺度上对其弹性描述符进行实验评价；Iii)这种高性能系统中高应变率灵敏度的预测本构建模。