چكيده به لاتين
Abstract
In this thesis, a field study of entrance geometry of Rajaee reservoir and its sedimentation patterns has been conducted and dimensionless equations for delta’s progression in reservoirs have been developed. The process depends on hydraulic, sediment and geometrical parameters of the reservoirs and their associated river. In this research, a number of effective parameters, such as water and sediment discharges in the river, the reservoir flow depth, and the entrance diverging angle of reservoir, has been investigated. At first, sedimentation processing in the reservoir has been studied using available bathymetries. In order to do this, after collecting the relevant bathymetries the sedimentation processing in the reservoir has been investigated using Civil3D and sedimentation volume and its progression was determined. The results showed the formation of delta in Rajaee reservoir. Investigation of bathymetries showed that until year 2008, 222 thousand cubic meters of reservoir volume was filled by sediments. Next, using the data of hydrometric stations flow-duration curves and sediment rating curves were extracted and sediment transport to the reservoir was studied. The progress speed of the delta’s pivot point was evaluated 40 meters per year. Comparing the slopes of topset and foreset parts of the delta in Rajaee dam’s reservoir, it was found that slope of the foreset part is approximately 6-8 times of the topset’s slope. Considering the transverse sections of the reservoir in years 1988 and 2008 and recorded section widths, the diverging angle was estimated 0.1 degree. In the end by using dimensional analysis, SPSS software for the five independent variables diverging angle of reservoir, time, water and sediment discharge and reservoir flow depth, a multiple linear regression model to field data is fitted for progression of pivot point.
Keywords: Filed Study, Diverging Angle, Delta Progression, Shahid Rajaee Reservoir, Civil3D, Spss
