Prediction and Control of Interface Damping in Built-up Structures

建筑结构界面阻尼的预测和控制

• 批准号: 1462870
• 负责人: Melih Eriten
• 金额: $ 25.16万
• 依托单位: University of Wisconsin-Madison
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-04-01 至 2018-03-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1462870&HistoricalAwards=false
• 关键词: Prediction; Control; Interface; Damping; Built

Interface damping is a primary source of energy losses in built-up structures such as weapon systems, space vehicles, aircrafts, ships, automobiles, buildings, bridges, and turbine engines. Accurate prediction and control of interface damping is critical for safety, reliability and energy efficiency of built-up structures operating in dynamic conditions. Interface damping results mainly from frictional energy losses over contacting surfaces. Variability, nonlinearity and uncertainty in contact interactions limit the ability to accurately predict and model interface damping. This research project aims at identifying the main mechanisms that govern interface damping, its magnitude and its nonlinear characteristics. The project will investigate and outline effective methods to adjust such characteristics to desired values. Results from this award will enable designs of structural interfaces with desired interface damping. The expected outcome is the improvement of safety, reliability and energy efficiency of built-up structures. The results from the research will be shared with the community and K 12, undergraduate and graduate students through design projects involving vibrations and acoustics of simple built-up structures.Time and load dependent stochastic interfacial events introduce nonlinearity to interface damping, and deter predictability of dynamical response. The current state-of-the-art in estimating interface damping is through phenomenological models, which cannot ensure predictive results for untested conditions. Physics-based models cannot account for all possible events and changes occurring at the interfaces. This research offers an effective alternative to complicated modeling whereby the mismatch of elastic properties across interfaces are adjusted, and loading conditions are identified to reduce and if possible eliminate nonlinearities and variability in interface damping. Additional benefit of this alternative approach is the ability to tune interface damping over several orders of magnitude based on operational needs. The research approach is a concerted effort in modeling and experimentation that bridges two distinct disciplines such as tribology and structural dynamics. The PI will systematically study interfacial mechanics, geometry, friction, material properties and loading conditions to identify the major contributors to interfacial energy dissipation. Built-up structures containing interfaces with controlled material properties, preloads and geometries will be designed and constructed. Finally, forced and free vibrations tests will be performed on the built-up structures to explore tunable interface damping in dynamic response. An education and outreach program will also be conducted to disseminate the research results to a broader audience, and introduce important concepts of damping and friction to the students at various stages of their education process.

接口阻尼是建筑结构中的能源损失的主要来源，例如武器系统，太空车辆，飞机，船只，汽车，建筑物，桥梁和涡轮机发动机。对界面阻尼的准确预测和控制对于在动态条件下运行的积累结构的安全性，可靠性和能源效率至关重要。界面阻尼主要来自接触表面上的摩擦能量损失。接触相互作用的可变性，非线性和不确定性限制了准确预测和模拟接口阻尼的能力。该研究项目旨在确定控制界面阻尼，其大小和非线性特征的主要机制。该项目将调查并概述有效方法，以调整此类特征为所需的值。该奖项的结果将使结构接口具有所需接口阻尼的设计。预期的结果是提高建筑结构的安全性，可靠性和能源效率。该研究的结果将与社区和K 12共享，本科生和研究生通过涉及振动和简单建筑结构的声学的设计项目。时间和依赖载荷随机界面事件引入了非线性，从而导致界面阻尼，并确定动态响应的可预测性。估计接口阻尼的最新目前是通过现象学模型，该模型无法确保未经测试条件的预测结果。基于物理的模型无法说明所有可能的事件和在接口处发生的变化。这项研究为复杂的建模提供了有效的替代方法，从而调整了跨接口的弹性特性的不匹配，并确定了加载条件以减少，并在可能的情况下消除界面阻尼的非线性和可变性。这种替代方法的额外好处是，根据运营需求，可以在几个数量级上调整接口接线。研究方法是在建模和实验中的一致努力，它桥接了两个不同的学科，例如摩擦学和结构动力学。 PI将系统地研究界面力学，几何形状，摩擦，材料特性和加载条件，以识别界面耗散的主要因素。将设计和构造包含具有受控材料特性，预加载和几何形状的接口的建筑结构。最后，将在构建结构上进行强制和自由振动测试，以探索动态响应中的可调接口阻尼。还将进行一项教育和外展计划，以将研究结果传播给更广泛的受众，并在其教育过程的各个阶段向学生介绍重要的抑郁和摩擦概念。