Assessing the Onset of Failure Through Acoustic Emission

通过声发射评估故障的发生

• 批准号: 9532061
• 负责人: Joseph Labuz
• 金额: $ 16.9万
• 依托单位: University of Minnesota-Twin Cities
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1996
• 资助国家: 美国
• 起止时间: 1996-05-15 至 2000-01-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9532061&HistoricalAwards=false
• 关键词: Assessing; Onset; Failure; Through; Acoustic

CMS-9532061 The failure of systems composed of brittle materials such as concrete and rock is controlled by the development and accumulation of microdefects referred to as damage. Macroscopically, damage reduces the elastic stiffness, causes anisotropy, and reduces the load-carrying capacity of the material. The objective of this research is to identify damage through the acoustic emission (AE) technique and to use this measurement of damage to assess the onset of failure in systems composed of rock-like materials. The accumulation of damage has a fundamental importance for defining the behavior of brittle materials in terms of their strength. In addition, the importance of detecting brittle failure of structures is brought on by the use of high-strength concrete, by the urgency in preserving classical monuments, and by the need to evaluate aggregate durability. It is claimed that a quantitative analysis of damage can be applied to components of full-scale structures by simplifying the deconvolution process for determining source mechanisms and orientations. The impact of this research on the infrastructure will be the real-time monitoring of systems to evaluate damage in the form of cracks, voids, loss of bond, and other detrimental processes leading to failure. ***

由混凝土和岩石等脆性材料组成的系统的破坏是由称为损伤的微缺陷的发展和积累控制的。从宏观上看，损伤降低了材料的弹性刚度，引起材料的各向异性，降低了材料的承载能力。本研究的目的是通过声发射（AE）技术识别损伤，并使用这种损伤测量来评估由岩石材料组成的系统的破坏开始。损伤的累积对于定义脆性材料的强度行为具有根本的重要性。此外，检测结构脆性破坏的重要性是由高强度混凝土的使用、保护古典古迹的紧迫性以及评估骨料耐久性的需要引起的。通过简化确定源机制和方向的反褶积过程，可以将损伤的定量分析应用于全尺寸结构的部件。这项研究对基础设施的影响将是对系统的实时监测，以评估裂缝、空隙、粘结损失和其他导致失效的有害过程的损害。＊＊＊