基于逆有限元方法和位移振型函数的薄板动载荷识别方法  

Identification of thin plate dynamic loads based on inverse finite element method and displacement mode shape functions

作　　者：李可路 肖龙飞[1,2,3] 刘明月[1,2,3] 寇雨丰[1] 魏汉迪 LI Kelu;XIAO Longfei;LIU Mingyue;KOU Yufeng;WEI Handi(State Key Laboratory of Ocean Engineering,Shanghai Jiao Tong University,Shanghai 200240,China;Institute of Marine Equipment,Shanghai Jiao Tong University,Shanghai 200240,China;Sanya Yazhou Bay Institute of Deepsea Science and Technology,Shanghai Jiao Tong University,Sanya 572024,China)

机构地区：[1]上海交通大学海洋工程国家重点实验室,上海200240 [2]上海交通大学海洋装备研究院,上海200240 [3]上海交通大学三亚崖州湾深海科技研究院,海南三亚572024

出　　处：《振动与冲击》2024年第21期284-290,共7页Journal of Vibration and Shock

基　　金：国家自然科学基金项目(52031006,42206192);深远海全天候驻留浮式研究设施研发专项(SSZX22002)。

摘　　要：动载荷识别对于结构设计和健康监测具有重要意义。利用在工程实践中容易获得的应变响应,提出了一种基于逆有限元方法和位移振型函数的薄板动载荷识别方法,能够同时识别动载荷空间分布和时间历程。首先,逆有限元方法可以利用离散应变数据重建离散位移场。然后,采用位移振型函数拟合得到连续位移场,将拟合良好的振型函数代入薄板微分控制方程中确定识别载荷。最后,通过薄板集中载荷和全局分布载荷识别的两个数值算例,验证该方法的可行性和准确性。结果表明,提出方法对于薄板动载荷的识别是有效且准确的。Dynamic load identification is of great significance for structural design and health monitoring.Here,a thin plate dynamic load identification method based on inverse finite element method(iFEM)and displacement mode shape functions was proposed using strain responses easily obtained in engineering practice.It could simultaneously identify spatial distribution and time history of dynamic loads.Firstly,iFEM could be used to reconstruct discrete displacement field with discrete strain data.Then,the discrete displacement field and displacement mode shape functions were used to fit the continuous displacement field,and the well fitted mode shape functions were substituted into thin plate vibration differential governing equations to determine dynamic loads to be identified.Finally,the feasibility and accuracy of this method were verified with two numerical examples of identifying concentrated loads and globally distributed loads on thin plate.The results showed that the proposed method is effective and accurate for identifying dynamic loads on thin plate.

关 键 词：动载荷识别 应变响应 薄板 逆有限元方法 位移振型 

分 类 号：TH212[机械工程—机械制造及自动化] TH213.3