نوع مقاله : مقاله پژوهشی
1 دانشجوی دکترا، گروه مهندسی آب، دانشگاه لرستان، خرمآباد
2 . مربی پژوهشکده حفاظت خاک و آبخیزداری، تهران
3 دانشیار گروه مهندسی آب، دانشگاه لرستان، خرمآباد
4 گروه آب و خاک، دانشگاه صنعتی شاهرود، شاهرود، ایران،
5 گروه هیدرولوژی، دانشگاه شهید چمران اهواز، ایران
عنوان مقاله [English]
Estimation of the sediment load which a specific flow is capable to transport, is one of the main topics of sediment researches. Abhar Rood River is one of the major rivers in Zanjan province which plays a big role in the agriculture of the region. In the present research, HEC-RAS 4.1 model is utilized to simulate the sediment hydraulic in Abhar Rood River. For this purpose, 730 sections along 50 km of Abhar Rood have been prepared by using the DEM map of the river (map scale 1:4000) in Hec-GeoRas extension of ArcMap, thereafter it was used to introduce the river geometry information to Hec-RAS model. Also the discharge amount with 25 years return period has been calculated in HYFA model using the 33 years flooding discharge data which was measured at the Ghorveh hydrometric station and used to simulate hydraulic flow of the Abhar Rood River. After calibrating the model for hydraulic conditions of the river, sediment boundary condition and bed gradation have been defined in model. Thereafter the sediment transport capacity of the river was calculated by transport functions at total cross sections. The comparison between the achieved results and measured data shows that, the Yang equation has minimum error compared with other equations. Therefore Yang equation due to its acceptable results is recommended to recognize the sediment transport capacity potential. In addition, to investigate the erosion and sedimentation status of Abhar Rood River, Hjulstrum and Shields criteria have been utilized. The hydraulic condition of this river shows the erosion status at the whole crosses of the river.