温度变化对正交索网结构非线性振动的影响

正交索网结构作为屋盖支承体系有着广泛的应用,属于一种柔性结构,对外荷载的作用比较敏感.非线性自振特性的研究对于正交索网结构在风荷载作用下的响应分析具有重要意义.本文考虑温度变化及几何非线性影响,采用连续化理论导出了正交索网结构非线性振动方程.通过Galerkin原理,将偏微分方程转化为常微分方程,并采用改进的L-P法对常微分方程进行了求解.结合算例讨论分析了温度变化、振幅等因素对正交索网结构非线性振动的影响.算例表明,正交索网结构固有频率随着温度的升高而减小,自振频率密集,具有较强的非线性,其自振频率随着振幅发生变化,其非线性振动呈现"硬弹簧"特性,正交索网结构的非线性自振频率高于线性频率.

Effect of temperature variation on the nonlinear vibration of orthogonal cable net structure

Orthogonal cable net structure is one of the supporting systems widely used for roof.As a type of flexible structure,it is sensitive to exterior loading.The research on nonlinear vibration property is of vital importance for further investigation on the wind-induced responses of cable net.Taking the temperature effect and geometric nonlinearity into consideration,the nonlinear vibration equation of orthogonal cable net was derived by assuming the support system as continuum.By the Galerkin principle,the par...