考虑质量偏心的阶梯梁-基础的强迫振动计算

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振动与冲击 ›› 2017, Vol. 36 ›› Issue (22) : 118-124.

论文

王剑1,2，张振果1,2，任龙龙1,2，华宏星1,2

作者信息 +

Forced Vibration Calculation of the Eccentric Stepped Beam-Foundation System

WANG Jian1, 2 ZHANG Zhen-guo1, 2 REN Long-long1, 2 HUA Hong-xing1, 2

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文章历史 +

摘要

轴系的质量非均匀会导致纵横振动的耦合，本文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。

Abstract

The vibrations in vertical and longitudinal directions will couple if mass eccentricities are considered in the beam, a theoretical/experimental method focus on the vibration of eccentric stepped beam-complicated flexible foundation system is proposed combining the receptance coupling and modified transfer matrix method. The method is validated via the comparison to the results obtained by the FEM. The influence on the response of the system caused by eccentricity is investigated. Eccentricity can hardly affect the vertical response of the system, while it can induce displacement in longitudinal direction even the beam is under vertical excitation. The longitudinal vibration is introduced by the form of eθ, therefore, the associated longitudinal displacement is proportional to eccentricity and its characteristic frequencies are consistent with that of the vertical displacement.

导出引用

王剑1,2，张振果1,2，任龙龙1,2，华宏星1,2. 考虑质量偏心的阶梯梁-基础的强迫振动计算[J]. 振动与冲击, 2017, 36(22): 118-124

WANG Jian1, 2 ZHANG Zhen-guo1, 2 REN Long-long1, 2 HUA Hong-xing1, 2. Forced Vibration Calculation of the Eccentric Stepped Beam-Foundation System[J]. Journal of Vibration and Shock, 2017, 36(22): 118-124

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