基于结构两相流模型计算泥石流对路基的冲击力

Calculation of impact force of debris flow on subgrade based on the model of conceptual two-phase flow

为了减轻山区公路路基遭受泥石流破坏的程度,为公路部门的防灾减灾提供科学指导,文章基于结构两相流模型计算了位于泥石流流通区出口以外一定距离的路基所受到的泥石流冲击力。首先通过受力分析求解了泥石流固液分相受到的摩擦阻力,在参考已有关于固液分相流速计算方法的基础上,根据能量守恒原理解出了位于泥石流出山口一定距离之外的路基处的固液分相流速;然后根据牛顿第二定律,得到了路基处的固液分相冲击力。该方法的准确性可以通过模型试验或现场实测进行检验并予以修正,所得结论可以用于指导山区公路路基的防护,对防治泥石流灾害具有参考意义。

The impact force of debris flow which was on the subgrade at a certain distance away from the exit of the debris flow was calculated based on the model of conceptual two-phase flow. The purpose of the study was to ease the destruct degree of rural highway subgrade and to provide scientific guidance for highway departments’ disaster prevention and mitigation. Firstly, the friction forces of solid phase and liquid phase were solved through force analysis. And on the basis of the method to calculate velocities of solid-liquid phase in debris flow, the velocities of solid-liquid phase at the subgrade were calculated based on the theory of conservation of energy. Then the impact forces of solid phase and liquid phase were solved based on Newton’s second law. The accuracy of this method can be tested and modified through model experiments and field tests. This method is valuable for the protection of highway subgrade and the prevention of debris flow disaster.