If the flood wave is deformed on its way of propagation, there exists acceleration term or inertia force that equals to internal friction.

波体在传播途中变形，则有加速项或惯性力，内摩阻力等于惯性力。

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When the sample is at the stage of grinding damage, the axial force and torque are related to the Young? S modulus, cohesion and internal friction Angle except the compression strength.

而处于研磨阶段时，轴向压力、扭矩和试样弹性模量、黏聚力及内摩擦角有关，与抗压强度无关。

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