Hydrodynamic Load on a Pervious Slab with Keyways in a Stilling Basin Lining

The stability of lining slabs in stilling basins is crucial for ensuring safety during flood discharge from large dams. Accordingly, this paper compares the stability of pervious slabs featuring keyways to impervious slabs without and with keyways. The experimental results demonstrate that the maximum uplift force exerted on pervious slabs with keyways and its standard deviation was less than that exerted on the other two types of slabs because the fluctuating pressure beneath the pervious slabs with keyways was considerably lower than that beneath the traditional slabs. The keyways strengthened the interaction between the slabs and lengthened the propagation route of the pressure fluctuations. The pressure fluctuations acting on the upper face and beneath the lower face of the pervious slabs tended to be in phase due to the propagation of the fluctuating pressure through the holes. The proposed pervious slabs with keyways could considerably increase the stability of the lining slabs in stilling basins.