(Solved): The longitudinal section below shows a single 15001200mm high concrete portal culvert under ...

The longitudinal section below shows a single $1500\times 1200\mathrm{mm}$ high concrete portal culvert under a freeway. The culvert is laid at a slope of $2.8\%$ and has wingwalls at $45^{?}$ which gives an entrance loss coefficient of 0,2 . The water surface elevations upstream and downstream are 24,320 and 21,820 respectively as shown. The invert level on centerline is 20,698 as shown. Manning's roughness coefficient $=0,012$. 1. Calculate the invert levels at points "a" and at "b" respectively. 2. Calculate the discharge (Q) in ${\mathrm{m}}^3/\mathrm{s}$ through the culvert, under outlet control, conditions, as well as the outlet velocity for the conditions given. 3. Calculate the headwater depth (HW) above the point "b"