Intensity – Duration – Frequency Analysis for Rainfall in Baiji Station

Abstract

In the present study, modified relations were obtained to relate rainfall intensity with frequency using Weibull method for 15, 30 and 60 minutes duration. This was done to estimate the designed value for rainfall intensity for any mentioned duration at any observation interval. The obtained results show that the rainfall intensity increases with the increasing of return period. Also, for every duration rainfall, the intensity decreases with the increasing of duration. Two types of probability distribution tests were applied for any duration, they are Gumble and Person (III) tests, also, statistical tests were applied to determine the optimum and suitable distribution for the studied data. The obtained relations can be usefull as a design equation for small weirs, culverts and rain downsrtream systems in the case of construction of them in the studied area.

Keywords

• Duration
• Frequency
• Rainfall
• Statistical analysis
• Storm analysis