一类单自由度分段光滑悬索桥模型的动力学研究  

Dynamic study on the suspension bridge model of single-degree-of-freedom piecewise smoothness

作　　者：侯林森 李高磊 吴鑫 乐源[1] HOU Linsen;LI Gaolei;WU Xin;YUE Yuan(Applied Mechanics and Structure Safety Key Laboratory of Sichuan Province,School of Mechanics and Aerospace Engineering,Southwest Jiaotong University,Chengdu 610031,China)

机构地区：[1]西南交通大学力学与航空航天学院应用力学与结构安全四川省重点实验室,成都610031

出　　处：《重庆理工大学学报（自然科学）》2023年第3期119-128,共10页Journal of Chongqing University of Technology：Natural Science

基　　金：国家自然科学基金项目(12072291,11732014)。

摘　　要：悬索桥受自身灵活性高但不够坚固的特性影响,其抗风能力相对较弱,当风速达到一定规模时,桥体可能会发生抖振、颤振甚至坍塌。研究了一类单自由度分段光滑的悬索桥模型受到风载荷作用时的动力学特性,数值模拟出系统在不同参数下的分岔图,吸引子和吸引域,得到丰富的多稳态现象。利用打靶法计算出系统的不稳定周期轨道,观察包括内部激变、边界激变在内的激变动力学现象。数值研究结果说明:同样的系统参数下可能出现多个运动状态,甚至出现从不稳定的周期运动状态直接跳跃到混沌的运动状态的现象,这在实际建造设计、安全性检测以及失效预警过程中需要注意或者避免。Affected by the fact that they are flexible but not strong enough,suspension bridges are less resistant to wind.When the wind speed reaches a certain scale,the bridge body may shake,flutter and even collapse.This paper analyzes the dynamic characteristics of a single-degree-of-freedom piecewise smooth suspension bridge model under wind loads,numerically simulates the bifurcation diagrams,attractors and attraction domains of the system under different parameters,and obtains multi-stable coexistence phenomena.The shooting method is used to calculate unstable periodic orbits of the system and observe the dynamic phenomena of crises,including internal and boundary crises.The numerical research results show that,under the same system parameters,multiple moving states may occur,and even the phenomenon of jumping directly from the unstable periodic motion state to the chaotic motion state may appear,which needs to be noted or avoided in the actual construction design,safety detection and failure warning.

关 键 词：非光滑系统 全局动力学 分岔 激变 混沌 

分 类 号：O313[理学—一般力学与力学基础]