Page - 477 - in Book of Full Papers - Symposium Hydro Engineering

COMMISSION INTERNATIONALE DES GRANDS BARRAGES ------- VINGT-SIXIÈME CONGRÈS DES GRANDS BARRAGES Autriche, juillet 2018 ------- DETERMINATION OF GERMI CHAY DAM RESERVOIR SEDIMENTATION PROCESS S. SHAHRADFAR Expert of Dam department, ASHENAB CONSULTING ENGINEERS SH. PARTOVI AZAR Expert of Dam department, ASHENAB CONSULTING ENGINEERS S. AHMADI ADLI M.Sc Student of Water Structures Engineering, FACULTY OF AGRICULTURAL ENGINEERING, TABRIZ UNIVERSITY IRAN 1. INTRODUCTION Prediction of sediment distribution in reservoirs is an important issue for dam designers to determine the reservoir active storage capacity, outlet sill elevation, dam stability, recreational facilities, and backwater conditions. A lot of methods such as physical, mathematical and experimental models are provided in this field. One of the most important experimental methods to study sediment distribution in the reservoir is area reduction method. Several mathematical models for predicting reservoir sedimentation have been developed based on the equations of motion and continuity for water and sediment. Some of these models have additional specific features such as the GSTARS which is developed Molinas and Yang (1986). In this research, GSTARS3 sediment transport model and areareduction method was used to simulate sedimentation processes in Germi Chay dam reservoir. Germi chai dam is a multi-purpose earth-fill dam with central clay core 477