冲击载荷作用下柱壳链中的弹性波传播简化模型及其解析解

柱壳链能引起波形的弥散，具备操控波形的潜力。建立了柱壳链结构的等效连续介质模型和细观有限元模型，研究了质量块冲击作用下柱壳链中的弹性应力波传播过程及其几何弥散特性。基于考虑横向惯性修正的Rayleigh-Love波动方程，建立了柱壳链在质量块冲击下的控制方程，采用Laplace变换及其逆变换获得了位移场、速度场和应变场的解析解，所得结果与细观有限元模拟结果较好吻合。结果表明，在冲击过程中应变和速度峰值均逐渐减小，应变峰值、振荡幅度和波形前沿宽度与泊松比和惯性半径相关，泊松比和惯性半径越大，应变峰值越小，应变分布振荡越剧烈，波形前沿宽度越宽。

Simplified model of elastic wave propagation in cylindrical shell chain under impact load and its analytical solution

Cylindrical shell chain can cause dispersion of waveform and has the potential to manipulate waveform. An equivalent continuum model and a mesoscopic finite element model of cylindrical shell chain structure were established, and the stress wave propagation process and its geometric dispersion characteristics in cylindrical shell chains under mass impact were studied. For the in-plane compression of a single cylindrical shell, the deformation in the out-of-plane direction is very small and the in-plane deformation perpendicular to the loading direction is relatively large. Thus, the out-of-plane Poisson’s ratio can be taken as 0, but the in-plane one cannot be ignored. For the simplification of analysis, the cylindrical shell chain is considered as a rod composed of anisotropic homogeneous continuum. Based on the Rayleigh-Love wave equation with the transverse inertia correction, the governing equation of elastic wave propagation in a cylindrical shell chain under mass impact was obtained and rewritten in a dimensionless form. The analytical solutions of displacement, velocity and strain fields were obtained by using Laplace transform and its inverse transform and expressed in the form of infinite series. A chain with 30 cylindrical shells was constructed numerically and its dynamic impact behavior was simulated with finite element code ABAQUS/Explicit. The theoretical predictions of mechanical responses are in good agreement with the results of mesoscopic finite element simulation. During the impact process, the peak values of strain and velocity decrease gradually. The peak strain, the oscillation amplitude of waveform and the width of waveform front are related to the in-plane Poisson's ratio and the radius of gyration of the cylindrical shell chain. The larger the in-plane Poisson's ratio and the radius of gyration of the cylindrical shell chain, the smaller the peak strain, the stronger the oscillation of the strain waveform and the wider the width of the waveform front.