Experimental investigation of the efficiency of stone revetment for different temporal variations with the static water condition

Abstract

The objective of this study is to determine the optimum size of stone revetment for different water standing durations and critical drawdown rates for 80% height of flood. The model bank was constructed using soil sourced from the Parlalpur ferry ghat of the Ganga River in Kaliachak, West Bengal, with a field density of 1,500 kg/m3 achieved by maintaining a 10% moisture content (MC) in the model bank soil. The model riverbank was prepared considering Froude (F) similitude having a distorted depth scale of 1/20 and a linear scale of 1/200. In this study, effective stone sizes (D10) – 2.33, 3.22, 4.58, 6.31, and 8.84 mm – were used. These stone sizes were investigated in conjunction with three water standing durations: 15, 30, and 45 min. The bank slope was prepared at 1V:1.5H, and a drawdown ratio of 80% was maintained. The effectiveness of stone revetment size was analysed in terms of the percentage loss of stone revetment and the percentage loss of the model bank's cross-sectional area. The outcomes of this study indicate that the 6.31 mm stone size exhibits optimal performance. HIGHLIGHTS Optimized stone size was determined.; This underscores the importance of careful stone selection, considering soil characteristics.; The findings of this study offer valuable insights into the temporal dynamics of bank stability under real-world hydrological conditions, which are beneficial for engineers.; The importance of synergetic impact of drawdown and velocity for designing the stone revetment for river bank protection.;

Keywords

• drawdown
• model river bank
• stone diameter
• stone revetment