High‐flow intensity over a well‐developed static armour layer will significantly reduce the stability of a riverbed. However, the intensity at which the static armour layer would completely break is not known. In this study, laboratory flume experiments were conducted to analyze the response of the static armour layer to high‐flow intensity. The static armour layer was developed under the condition of steady flow with no supply of sediments. The flow intensity was increased by increasing the flow discharge, and the bed‐load rate was determined to evaluate whether the static armour layer broke. The observations indicate that when the bed shear stress is low (<1.2 times the initial bed shear stress of the pre‐armoured bed), the bed‐load transport rate is low and the mobility of the static armour layer is constrained. However, when the bed shear stress increases to 1.2 times the initial bed shear stress, the bed‐load transport rate increases, and the mobility is significantly promoted, indicating that the layer is broken. In our experiments, the characteristic particle sizes of the bed, D₅₀ and D₈₄, changed slightly before the static armour layer was broken, which signified that the composition of the riverbed slightly changed. However, the effect of the bed structure gradually increases with the increase in the flow intensity, leading to a 20% increase in the stability threshold of the static armour layer. In addition, the time to re‐form the new static armour layer after the destruction of the old one was observed to be positively correlated with flow intensity. However, further research must be conducted on the threshold of the damage of the static armour layer.

中文翻译：

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静态铠装层临界破坏条件的实验研究

发达的静态装甲层上的高流量强度将大大降低河床的稳定性。但是，静态铠装层完全破裂的强度尚不清楚。在这项研究中，进行了实验室水槽实验以分析静态铠装层对高流动强度的响应。静态装甲层是在稳定流动且没有沉积物供应的条件下开发的。通过增加流量来增加流量强度，并确定床荷率以评估静态铠装层是否破裂。观测结果表明，当床层剪应力低（<1.2倍于预装甲床的初始床层剪应力）时，床层荷载输送率就低，并且静态装甲层的活动性受到限制。然而，当床层剪切应力增加到初始床层剪切应力的1.2倍时，床层荷载传输速率增加，迁移率显着提高，表明该层已破裂。在我们的实验中，床的特征粒径在静态铠装层破裂之前，D ₅₀和D ₈₄略有变化，这表明河床的成分略有变化。然而，随着流动强度的增加，床结构的作用逐渐增加，导致静态铠装层的稳定性阈值增加20％。此外，观察到旧的防弹层被破坏后重新形成新的静态防弹层的时间与流动强度呈正相关。但是，必须对静态铠装层的损伤阈值进行进一步的研究。