摘要
向量式有限元(VFIFE)可以有效分析模拟柔性结构大变形、非线性或不连续力学行为,无须组集整体刚度矩阵,因而无法直接利用特征值求解得到模态参数。本文基于随机子空间识别方法(SSI),在VFIFE求解程序中嵌套基于协方差的随机子空间识别程序(VFIFE-SSI),分别对孪生索-索网体系和异索-索网体系的VFIFE模型进行模态识别,得到索网结构的模态频率、阻尼比和振型,通过对比解析解和传统有限元求解结果,验证了VFIFE-SSI方法的准确性。分析结果表明,辅助索的刚度和阻尼系数会影响索网结构的模态参数,工程中可以通过调节辅助索参数来调整索网整体性能。
The vector form intrinsic finite element method(VFIFE) is suitable for analyzing and simulating the large deformation, nonlinear or discontinuous mechanical behaviors of the flexible structures effectively, without assembling the global stiffness matrix. As for that, the modal parameters cannot be solved by eigenvalues directly. In this paper, referring to the stochastic subspace identification(SSI), the covariance based stochastic subspace Identification program(VFIFE-SSI) is nested in the VFIFE solver. The modal analyses of the twin-cable network and the different cables network VFIFE models are carried out respectively, and the modal frequencies, damping ratios and mode shapes of the cable network are obtained. The accuracy of the VFIFE-SSI method is verified by comparing the results of the analytical solution with the traditional finite element analysis results. Meanwhile, the results show that the stiffness and damping coefficient of the cross-ties will influence the modal parameters of the cable network, and the overall performance of the cable network can be adjusted by varying the cross-tie parameters in engineering.
作者
黄嘉思
徐文城
段元锋
章红梅
HUANG Jiasi;XU Wencheng;DUAN Yuanfeng;ZHANG Hongmei(College of Civil Engineering and Architecture,Zhejiang University,Hangzhou 310058,China;CCCC Highway Consultants Co.,Ltd.,Beijing 100088,China)
出处
《结构工程师》
2022年第6期1-6,共6页
Structural Engineers
基金
国家重点研发计划项目(2019YFE0112600,2018YFE0125400)
国家自然科学基金项目(U1709216,52078459)
中央高校基本科研业务费专项资金资助(2020QNA4018)。
关键词
向量式有限元
随机子空间识别
模态分析
索网
vector form intrinsic finite element(VFIFE)
stochastic subspace identification(SSI)
modal analysis
cable network
