EAGER: A Reassessment of the Notion of Damage of Materials

EAGER：对材料损坏概念的重新评估

基本信息

批准号：
1647537
负责人：
Kumbakonam Rajagopal
金额：
$ 8.25万
依托单位：
Texas A&M Engineering Experiment Station
依托单位国家：
美国
项目类别：
Standard Grant
财政年份：
2016
资助国家：
美国
起止时间：
2016-09-01 至 2019-08-31
项目状态：
已结题

来源：
https://www.nsf.gov/awardsearch/showAward?AWD_ID=1647537&HistoricalAwards=false
关键词：
EAGER Reassessment Notion Damage Materials

项目摘要

This EArly-concept Grant for Exploratory Research (EAGER) award investigates a radically different approach to represent the damage of materials that can potentially transform the field of mechanics. The assessment and remediation of damage in structural materials is a critically important issue facing scientists and engineers. The consequences of damage due to thermal cycling, moisture, electromagnetic radiation, and cyclical mechanical loading on dams, bridges, tunnels and buildings can be catastrophic. However, predicting the remaining lifetime of these structural components is challenging due to the need to know the history of these applied loads. The research will provide a new representation for the prediction of damage growth based on quantities, such as the density of the body, that are completely determined by the current configuration of the body. Such an approach is meaningful for a large class of polymeric materials and brittle materials such as concrete. If successful, the research will have a significant impact on numerous problems that have technological significance for the assessment and remediation of damage in materials and structures.Most of the current methodologies to assess damage resort to using effective damage parameters that invariably lack proper physical interpretation. Complicating matters further is the use of criteria for damage based on quantities such as stress or strain, quantities whose values cannot necessarily be decided based on the current state of the body. It would be much more meaningful and appropriate to use values of quantities that are completely determined by the current state of the body rather than the relative value of a physical quantity that requires information from a special reference state. Examples of quantities that are completely determined in the current state are the density, temperature, microstructural features, etc. The aim of the research is to take into account such quantities in the current state of the body to develop constitutive relations that can meaningfully predict the onset of damage.

这项早期概念探索性研究资助 (EAGER) 奖项研究了一种完全不同的方法来表示材料的损伤，有可能改变力学领域。结构材料损伤的评估和修复是科学家和工程师面临的一个至关重要的问题。热循环、湿气、电磁辐射和循环机械载荷对水坝、桥梁、隧道和建筑物造成的损害后果可能是灾难性的。然而，由于需要了解这些施加载荷的历史记录，预测这些结构部件的剩余寿命具有挑战性。该研究将为基于数量（例如完全由身体当前配置决定的身体密度）的损伤增长预测提供新的表示。这种方法对于一大类聚合物材料和脆性材料（例如混凝土）有意义。如果成功，这项研究将对许多问题产生重大影响，这些问题对于材料和结构损伤的评估和修复具有技术意义。目前大多数评估损伤的方法都采用有效的损伤参数，而这些参数总是缺乏适当的物理解释。使问题进一步复杂化的是使用基于应力或应变等量的损伤标准，这些量的值不一定根据身体的当前状态来确定。使用完全由身体当前状态决定的量值，而不是需要来自特殊参考状态的信息的物理量的相对值，会更有意义和更合适。在当前状态下完全确定的量的例子有密度、温度、微观结构特征等。研究的目的是考虑物体当前状态下的这些量，以开发可以有意义地预测的本构关系。损害的发生。