螺栓连接大变形梁振动特性的实验与数值研究  

Experimental and numerical study on vibration characteristics of bolted large deformed beams

作　　者：张珂 王顺增 江俊[1] Zhang Ke;Wang Shunzeng;Jiang Jun(State Key Laboratory for Strength and Vibration of Mechanical Structures,Xi'an Jiaotong University,710049,Xi'an,China)

机构地区：[1]西安交通大学航天航空学院机械结构强度与振动国家重点实验室,西安710049

出　　处：《应用力学学报》2021年第2期497-505,共9页Chinese Journal of Applied Mechanics

基　　金：国家自然科学基金(11772243;11672218)。

摘　　要：螺栓连接的柔性梁既有非线性又有几何非线性,本文针对其动力学建模和振动特性开展了实验与数值研究。首先,搭建了含螺栓连接的柔性大变形梁的实验台架,并开展敲击和正弦激振的实验测试。实验结果表明:螺栓连接的柔性梁较(无螺栓连接的)连续梁的模态频率降低,阻尼增加,呈现出随着激励能量增大,模态频率降低的非线性模态特征。其次,为了建立大变形柔性梁的有效计算模型,采用了动坐标迭代法,并采用改进Iwan模型和库仑摩擦模型刻画连接部件的力学特性。最后,开展了数值计算,通过与实验测试结果对比表明:数值计算结果与实验测试结果误差在7%以内,所建立的柔性连接梁的计算模型能够有效准确地模拟含连接部件柔性梁的非线性模态和动力学响应特征。To exploit the dynamic model and the vibration characteristics of the bolted flexible beams, which have both joint and geometric nonlinearity, both experimental and numerical studies are carried out in this paper. Firstly, a test bench of a bolted flexible beam is built, by which the large deformation responses of the beam under tapping and sinusoidal excitation are measured. It is shown that the decrease of modal frequencies and the increase of damping result in the bolt-jointed flexible beam with the increase of excitation energy in comparison with the flexible beam without bolt-joint, which shows the nonlinear modal characteristics. After modeling the bolt-joint by the adjusted-Iwan model and the Coulomb model, an effective finite element model for the flexible beam with large deformation is established through the floating coordinate method. The error between the numerical calculation result and the experimental test result is within 7%. The simulation results indicate that the nonlinear modal characters and dynamic responses of the flexible beam with bolted-joint can be accurately predicted.

关 键 词：螺栓连接 大变形梁 非线性模态 动力响应 

分 类 号：O32[理学—一般力学与力学基础]