Application of Unsteady Approach in Determination of Design Parameters of Underground Drainage System (Case Study: Experimental Farm of Human Resources and Agricultural Development Center, Mazandaran, Iran)

摘要

For drying paddy soils, underground drainage system is imperative and the application of theoretical equations in design of underground drainage system is not efficient for all farms, either, therefore, the construction of experimental farms prior to the massive construction projects is inevitable. To determine the underground drainage system parameters in paddy experimental fields of human resources and agricultural development center of Mazandaran Province, Iran, becomes to the main goal of this study. Owing to the excessive rainfall in these regions, the fluctuation of water with its corresponding none-steady state happens. To achieve the goal on the construction of experimental farms, underground water surface level was measured in an area of about 11700 square meters, equipped with underground drainage system in 15 meters distance and 70 centimeters depth. Tests onthe soil texture with its hydraulic conductivity were additionally conducted in these regions. Regarding to the proper reaction of the drainage system to the precipitation events, the most efficient underground drainage system was derived for the adjacent area with relevant results of the immediate reaction ratio and specific discharge.