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仅取决于卓越的强度，还取决于耗散能量和吸收冲击的机制的组合。 众所周知，轻质固体和离散加固等战略夹杂物会局部失效，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大多仍然是宏观的，并且组件尺度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水泥基复合材料中的负载率效应，并具体完成： i）此类系统中能量耗散机制的 2-D 和 3-D 量化； ii) 在微观、中观和宏观尺度上对其复原力描述符进行实验评估； iii）此类高性能系统中高应变率敏感性的预测本构模型。 该提案将整合我们对水泥材料动态裂纹扩展和止裂过程的理解，这些材料已在标准测试下证明具有较高的性能重量比。将采用断裂试验和无损技术的结合来量化水泥基复合材料对动态载荷的体积响应。预计该结果将有助于了解异质脆性基质系统的速率敏感性，并产生具有多尺度能量耗散的减震系统。 4名研究生研究助理（1名博士和3名硕士）和5名本科生将加入研究团队。他们将与相关领域的研究人员互动。通过多元化学生研究人员的参与，新一代高素质人员将被介绍使用高应变率测试、无损技术、计算模拟和高性能结构材料。