: High-yield strength deformed bars (e.g., Fe 500 ). Dimensions : Determine the clear span ( ) and rise ( ) based on hydraulic requirements. Soil Parameters : Angle of internal friction ( , typically 30∘30 raised to the composed with power ), unit weight of soil ( γsgamma sub s , approx. ), and unit weight of concrete ( γcgamma sub c , ). 📐 Primary Design Steps 1. Load Calculations
: Calculated using the active earth pressure coefficient ( Kacap K sub a box culvert design calculations pdf
[ Q = \frac1n A R^2/3 S^1/2 ]