This paper investigates the nonlinear free vibration and nonlinear dynamic hygrothermal buckling behavior of imperfect functionally graded carbon nanotube-reinforced composite (FG-CNTRC) cylindrical panels under hygrothermal environment. The nonlinear temperature distribution is assumed along the thickness direction. The structure is resting on a generalized nonlinear viscoelastic foundation which is composed of a two-parameter Winkler-Pasternak foundation augmented by a Kelvin-Voigt viscoelastic model with a nonlinear cubic stiffness and damping considerations. The nonlinear von Kármán strain-displacement relations and the classical shell theory are considered to derive the governing equations of the cylindrical panels. The discretized equations of motion are obtained using the Galerkin method. The fourth order Runge-Kutta method is utilized to analyze the nonlinear dynamic hygrothermal buckling. The influences of the four CNTs distribution types, consist of the FG-O, FG-Λ, FG-X, and UD, are considered for the cylindrical panel. The effects of temperature, moisture, nonlinear viscoelastic foundations, initial imperfection, and material parameters on the nonlinear free vibration and nonlinear dynamic hygrothermal buckling behavior of the system are investigated.

本文研究了不完整的功能梯度碳纳米管增强复合材料（FG-CNTRC）圆柱面板在湿热环境下的非线性自由振动和非线性动态湿热屈曲行为。沿厚度方向假定为非线性温度分布。该结构位于广义非线性粘弹性基础上，该基础由两参数Winkler-Pasternak基础组成，基础上增加了具有非线性三次刚度和阻尼考虑因素的Kelvin-Voigt粘弹性模型。考虑了非线性vonKármán应变-位移关系和经典壳理论来推导圆柱面板的控制方程。使用Galerkin方法获得离散的运动方程。利用四阶Runge-Kutta方法对非线性动态湿热屈曲进行了分析。对于圆柱面板，考虑了由FG-O，FG-Λ，FG-X和UD组成的四种CNT分布类型的影响。研究了温度，湿度，非线性粘弹性地基，初始缺陷和材料参数对系统的非线性自由振动和非线性动态湿热屈曲行为的影响。