Design and Stiffness-Damping Optimizatino of Hybrid Coomposite Laminated Structures

混合复合材料层合结构的设计与刚度阻尼优化

• 批准号: 1200506
• 负责人: Marwan Al-Haik
• 金额: $ 18万
• 依托单位: Virginia Polytechnic Institute and State University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-08-15 至 2015-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1200506&HistoricalAwards=false
• 关键词: Design; Stiffness; Damping; Optimizatino; Hybrid

This project aims at developing, optimizing and validating laminated hybrid composites that possess excellent damping and stiffness properties. The hybrid composites comprising both commercial carbon fibers and surface-grown carbon nanotubes (CNTs) offer attractive alternative to fiber reinforce composites (FRPs) and cheaper alternative to pristine CNTs composites. The hybrid composites also incorporate vanadium oxide (VO2) that exhibits a negative stiffness behavior in thermal environments induced by vibrations. We anticipate the hybrid composite to acquire high specific stiffness due to the CNTs? elevated stiffness (TPa level) while gaining enhanced damping through the negative stiffness of VO2 together with the inherent matrix viscoelastic damping properties. Finite element methods and multi-objective optimization environment will be employed to optimize the topology of the hybrid composites to yield superior stiffness and damping properties. To validate the hybrid composites? dynamics performance, laboratory controlled vibration tests will be carried out to exploit their responses to specific excitations. The analysis of data from these tests will be used for characterization and identification of the vibrating system parameters (damping, stiffness and nonlinear parameters).Vibrations can compromise the safety and durability of structural components FRPs. Despite their attractive mechanical properties, the low through-thickness mechanical properties of FRPs have restricted their application in structures to mitigate out-of plane dynamic loads. The developed hybrid composites with enhanced damping have an impact on applications that utilize FRP such as commercial and military aircraft frames (ex. Boeing 787 Dreamliner), ship vessels, auto industries, infrastructures and sport goods. Considering the emerging applications of FRPs in civil infrastcrtures (bridges, columns, etc..) the developed materials offer an attractive and practical solution to mitigate random vibrations such as those encountered in earthquakes also they can extend the fatigue life of these structures. The educational components of the project will benefit three departments in the Virginia Tech (VT) College of Engineering. One existing graduate courses will be revised to include both theoretical and hands-on modules based on the project tasks. One graduate student will participate hands-on in the synthesis, fabrication,characterization, topological optimization, vibration testing and parametric identification of the hybrid composites toward a Ph.D. degree.

该项目旨在开发、优化和验证具有优异阻尼和刚度特性的层压混合复合材料。由商业碳纤维和表面生长碳纳米管（CNT）组成的混合复合材料为纤维增强复合材料（FRP）提供了有吸引力的替代品，并且比原始碳纳米管复合材料提供了更便宜的替代品。该混合复合材料还包含氧化钒 (VO2)，它在振动引起的热环境中表现出负刚度行为。我们预计混合复合材料会因碳纳米管而获得高比刚度？提高刚度（TPa 水平），同时通过 VO2 的负刚度以及固有的基体粘弹性阻尼特性获得增强的阻尼。 将采用有限元方法和多目标优化环境来优化混合复合材料的拓扑，以产生优异的刚度和阻尼性能。 验证混合复合材料？为了提高动力学性能，将进行实验室控制振动测试，以利用它们对特定激励的响应。这些测试数据的分析将用于振动系统参数（阻尼、刚度和非线性参数）的表征和识别。振动会损害结构部件 FRP 的安全性和耐用性。尽管具有吸引人的机械性能，但 FRP 的低全厚度机械性能限制了其在结构中减轻平面外动态载荷的应用。所开发的具有增强阻尼的混合复合材料对利用 FRP 的应用产生了影响，例如商用和军用飞机框架（例如波音 787 梦想飞机）、船舶、汽车工业、基础设施和体育用品。 考虑到玻璃钢在民用基础设施（桥梁、柱子等）中的新兴应用，所开发的材料提供了一种有吸引力且实用的解决方案，可以减轻随机振动（例如地震中遇到的随机振动），还可以延长这些结构的疲劳寿命。该项目的教育部分将使弗吉尼亚理工大学 (VT) 工程学院的三个系受益。一门现有的研究生课程将根据项目任务进行修订，包括理论和实践模块。一名研究生将参与混合复合材料的合成、制造、表征、拓扑优化、振动测试和参数识别，以获得博士学位。程度。