الفهرس 
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Abstract
Reinforcement corrosion is the main cause of damage and early failure of reinforced concrete structures. The protection system of embedded steel reinforcement from chloride induced corrosion involves several methods and techniques, such as addition of corrosion inhibiting admixtures (CIA) to the concrete mixes, epoxy coated reinforcing steel, stainless steel, high quality concrete, and surface impregnation of concrete and cathodic protection. To achieve the purposes of this thesis, the test program was divided into two phases. In the first phase, the test program was arranged to determine the effect of compressive strength, concrete mixtures proportions and contents with different variables on corrosion rate of steel reinforcement in concrete. Various concrete cover (25, 50, 75 mm) were investigated. Also, investigation their effect on properties of concrete, these variables includes water to cement ratio, the effect of admixtures -silica fume and super plasticizer, cement type and their contents in concrete mixtures. In the second phase, the test program was arranged to determine the effect of corrosion inhibitors admixtures and epoxy coated reinforcing bars on corrosion rate of steel reinforcement in concrete with various concrete cover (25, 50, 75 mm) and properties of concrete. Two corrosion inhibitors were evaluated in this study, Sika Ferrogard® -901 and Calcium nitrite. Two Epoxy – coated reinforcing bars were evaluated in this study, Kema poxy 131 and Sika Zink rich-EG. The results show that for all mixes the increasing of concrete cover thickness reduces the corrosion rate of steel. Increasing compressive strength from 180 to 650 kg/cm2 reduces corrosion rate of steel by 67, 86 and 97% for concrete cover 25, 50 and 75 mm respectively. Increasing cement content in the concrete mix from 300 to 450 kg/m3 reduces corrosion rate of steel by 50, 52 and 60% for concrete cover 25, 50 and 75 mm respectively. Decreasing water to cement ratio from 0.65 to 0.35 reduces corrosion rate of steel by 54, 62 and 72% for concrete cover 25, 50 and 75 mm respectively. Increasing percent of silica fume by 15 % reduces corrosion rate of steel by 56, 60 and 87% for concrete cover 25, 50 and 75 mm respectively. The results show that the optimum dosage of corrosion inhibitors admixtures to concrete mixtures is 5% by weight of cement and there is no side effect on concrete properties except bond strength decrease by 10%. Using epoxy coated reinforcing bars reduces corrosion rate of steel by 93, 96 and 98 % for concrete cover 25, 50 and 75 mm respectively referred to control mix without coating.