The surrogate system hypothesis for joint mechanics
The surrogate system hypothesis for joint mechanics
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DOI：
10.1016/j.ymssp.2019.02.013
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发表时间：
2019-07
影响因子：
8.4
通讯作者：
N. N. Balaji-N.;M. Brake
中科院分区：
文献类型：
--
作者：
N. N. Balaji-N.;M. Brake
连接结构设计和分析中的主要挑战涉及跨螺栓界面的耗散预测。由于摩擦被认为是导致这一现象的主要机制之一，本研究调查了摩擦参数识别在不同结构中应用的实用性。基于最近的发现，提出了一个代理系统假说来系统化这一点：该假说简而言之地陈述了关节的物理属性与其结构背景无关。目前的工作试图通过评估一组相对简单的系统的假设的置信度度量来更好地了解潜在系统--制动-罗伊梁的物理扰动配置。界面摩擦采用具有分布滞回单元的整体节理片来模拟，并使用准静态模态分析(QSMA)方法进行仿真以估计系统响应的模态特性(固有频率和耗散的幅值相关性)。将估计问题归结为多目标优化问题(MOOP)，揭示了所采用的本构模型和所模拟的结构的重要特征。因此，该方法被用来评估三种不同摩擦模型中固有的认知不确定性。研究表明，假设的置信度度量可以用这样一种方式来表示，即它几乎独立于所采用的摩擦本构模型。
The main challenges in the design and analysis of jointed structures deal with the prediction of dissipation across bolted interfaces. Since friction is thought to be one of the main mechanisms for this, the current study investigates the utility of frictional parameter identification applied across different structures. Based on recent discoveries, a Surrogate System Hypothesis has been formulated to systematize this: the hypothesis states in brief, that the physical properties of a joint are independent of its structural context. The current work seeks to obtain a better understanding of the underlying systems by evaluating a confidence metric for the hypothesis for a relatively simple set of systems—physically perturbed configurations of the Brake-Reuß Beam. Interfacial friction is modeled using whole jointed patches with distributed hysteretic (Iwan) elements and simulations are conducted using the Quasi-Static Modal Analysis (QSMA) approach to estimate the modal characteristics of the system response (amplitude dependence of natural frequency and dissipation). Posing the estimation as a Multi-Objective Optimization Problem (MOOP) is shown to reveal important features of both the employed constitutive model as well as the structure that is modeled. Consequently, the approach is used to evaluate the epistemic uncertainty inherent in three different friction models. The studies reveal that a confidence metric for the hypothesis can be formulated in such a way that it is nearly independent of the friction constitutive model that is employed.