Lacey's regime equations, followed in India for making scour calculations while designing hydraulic structures across alluvial channels, are given below. Regarding these equations, which of the following statements is/are true:
$$ \begin{aligned} & D=0.470 \times\left[\frac{Q}{f_s}\right]^{1 / 3} \\ & P=4.75 \times \sqrt{Q} \\ & f_s=1.76 \times \sqrt{d} \end{aligned} $$
where, $Q$ is discharge and $f_s$ is silt factor
- A$D$ is the depth of scour below the existing riverbed
- B$P$ is the Lacey's waterway width
- C$d$ is the average grain size diameter of the bed material in centimetres
- D$D$ is the depth of scour below the design flood level
✓ Correct answer: B
Want the full step-by-step reasoning?