A probabilistic equation of design discharge for a mountainous gully was derived in terms of reliability probability. Its derivation was based on the rational formula, the rainfall-intensity-duration formula, and the First-Order Second-Moment method (FOSM) by considering the uncertainty of parameters, such as the annual rainfall, the runoff coefficient, the watershed area, the sediment concentration, the length and velocity of overland flow, and the horizontal length and elevation difference of a gully, involved in the formulas. The probabilistic equation was also applied to the probabilistic design discharge for a debris-flow-prone gully in Taiwan.
All Science Journal Classification (ASJC) codes
- Civil and Structural Engineering
- Water Science and Technology