Longitudinal elastic stress wave propagation through a 180° bend junction connecting two square bars is analyzed using analytical and numerical approaches and validated against experiments. The aim is to identify conditions under which the one-dimensional stress propagation principles can be applied to this geometry despite complete reversal of the stress wave path and study the mechanism of wave propagation through this geometry. By assuming the junction to move as a rigid body parallel to the input wave direction, the influence of the bend is analyzed for different pulse shapes and durations. For long duration stress pulses, the bend allows the stress wave to “flow” through the junction without distortion, whereas for short duration stress pulses, the wave undergoes significant dispersion. The junction behavior was further analyzed using finite element analysis and the results compared well with those of the analytical model. The wave motion through the junction results in asymmetric deformation of the junction, which generates flexural waves of different amplitudes in both the input and output bars. In general, stress pulses with constant peak amplitude and a smooth transition to the peak value suffer minimal dispersion as they traverse the junction. It is concluded that one-dimensional stress wave theory can be used to successfully model the propagation of long-duration longitudinal stress pulses around a 180° bend junction.

使用解析和数值方法分析通过连接两个方杆的 180° 弯曲接头的纵向弹性应力波传播，并通过实验进行验证。目的是确定在哪些条件下可以将一维应力传播原理应用于该几何形状，尽管应力波路径完全反转，并研究波通过该几何形状传播的机制。通过假设结以平行于输入波方向的刚体移动，分析了弯曲对不同脉冲形状和持续时间的影响。对于长持续时间的应力脉冲，弯曲允许应力波“流动”通过接合部而不会变形，而对于短持续时间的应力脉冲，波会经历显着的分散。使用有限元分析进一步分析了结行为，结果与分析模型的结果进行了很好的比较。通过结的波动导致结的不对称变形，从而在输入和输出条中产生不同幅度的弯曲波。一般来说，具有恒定峰值幅度和平滑过渡到峰值的应力脉冲在穿过结时的色散最小。得出的结论是，一维应力波理论可用于成功模拟长时间纵向应力脉冲在 180° 弯曲接头周围的传播。它在输入和输出条中产生不同幅度的弯曲波。一般来说，具有恒定峰值幅度和平滑过渡到峰值的应力脉冲在穿过结时的色散最小。得出的结论是，一维应力波理论可用于成功模拟长时间纵向应力脉冲在 180° 弯曲接头周围的传播。它在输入和输出条中产生不同幅度的弯曲波。一般来说，具有恒定峰值幅度和平滑过渡到峰值的应力脉冲在穿过结时的色散最小。得出的结论是，一维应力波理论可用于成功模拟长时间纵向应力脉冲在 180° 弯曲接头周围的传播。