考虑质量偏心的阶梯梁-基础的强迫振动计算  

Forced vibration calculation of an eccentric stepped beam-foundation system

作　　者：王剑 张振果[1,2] 任龙龙[1,2] 华宏星 

机构地区：[1]上海交通大学振动冲击噪声研究所,上海200240 [2]上海交通大学机械系统与振动国家重点实验室,上海200240

出　　处：《振动与冲击》2017年第22期118-124,共7页Journal of Vibration and Shock

基　　金：国家自然科学基金(51505281)

摘　　要：轴系的质量非均匀会导致纵横振动的耦合,结合导纳综合法与改进的传递矩阵法,针对质量偏心阶梯梁-弹性基础模型,提出了一种理论/实验混合计算方法。通过与有限元计算结果对比,验证了方法的正确性;考察了质量偏心对系统响应的影响。结果表明:在垂向激励下,质量偏心对系统的垂向位移响应无影响,但是会使系统产生纵向位移响应;由于纵向位移以eθ的形式被引入弯-纵耦合振动方程,因此其频率特征与垂向响应一致,且其幅值与偏心程度成正比。The vibrations in vertical and longitudinal directions will couple if mass eccentricities are considered in a beam. A theoretical/experimental method focusing on the vibration of an eccentric stepped beam-complicated flexible foundation system was proposed combining the receptance coupling and modified transfer matrix method. The method was validated via the comparison to the results obtained by the FEM. The influence on the response of the system caused by eccentricity was investigated. Eccentricity could hardly affect the vertical response of the system,while it could induce displacement in longitudinal direction even the beam was under vertical excitation. The longitudinal vibration was introduced by the form of eθ,therefore,the associated longitudinal displacement was proportional to eccentricity and its characteristic frequencies were consistent with that of the vertical displacement.

关 键 词：质量偏心 阶梯梁 弹性基础 导纳综合法 

分 类 号：TH113[机械工程—机械设计及理论]