Based on the incremental thermal field theory ,the nonlinear dynamic model of stay cables with thermal effects was established by introducing two non-dimensional parameters in the cable tension force and the sag ,and the nonlinear vibration equations of motion were derived by the Hamilton's principle . Under support excitation ,these differential equations were discretized by the Galerkin method .The first two in-plane and out-of-plane mode shapes were selected in forming the dynamic response and the Runge-Kutta method was used to solve these ordinary differential equations from forward sweeping to backward sweeping .The amplitude-frequency response curves of the numerical examples show that the natural frequencies decrease with temperature changes ;the resonance interval drifts ;the location of the jump point shifts ;the resonance response amplitudes change ;under the excitation of the support motions ,many more modes might be excited w hen the temperature is changed ,so the energy of different modes and the energy transfer between different modes varies under temperature changes .%基于增量热场理论,利用Hamilton变分原理,通过引入与张拉力和垂度相关的无量纲参数,建立了考虑温度变化影响下斜拉索非线性动力学模型,并推导其面内/外非线性运动微分方程.考虑斜拉索受端部激励,利用Galerkin法得到离散后的无穷维常微分方程组.面内和面外运动各取前两阶模态,向前和向后扫频,利用龙格-库塔法数值积分求解常微分方程组,得到共振区域的幅频响应曲线.算例分析表明,温度变化和斜拉索固有频率呈反比例关系;温度变化会导致斜拉索共振特性发生定性和定量的改变,如共振区间发生漂移、跳跃点位置发生移动、共振响应幅值发生改变;端部位移激励下,温度变化有可能导致斜拉索更多模态受到激发,从而影响各阶模态的能量以及模态间的能量传递.
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