الفهرس 
CHAPTER (1): INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
Concrete curing is one of the most important processes in achieving the desired properties of the concrete. The test cubes of any particular mix will immerse in water until the testing day in order to promote the hydration process of the concrete. The mixing water that used to manufacture concrete is not sufficient to perform hydration processes of cement in concrete to be hardened. So excessive amount of water as curing water to provide the required water to finish hydration processes was needed. Curing process may perform using different methods such as cover with wet gunnysack or plastic sheet to promote continuous hydration or we protect the initial water from evaporating. Sometimes engineers cannot perform concrete curing processes so there was a need to use self-curing type of concrete. Self-curing concrete as a new concrete is manufacturing using a self-curing agent who represents a new trend in the concrete construction in the new millennium. The concept of selfcuring agent is to reduce the water evaporation from concrete, which causes continuous cement hydration and consequently the achievement of the concrete strength together with good quality. As a new type of used concrete, there is a need to study its long-term properties. This research studied the properties of self-curing concrete due to chloride and sulfate ingress, corrosion potential characteristics. In addition, the effect of fire on the hardened properties studied. The effect of sulfate on the mechanical properties of self-curing concrete was investigated. A number of twelve cubes of dimensions 10x10x10 cm used to evaluate compressive strength, a number of twelve cylinders of 10x20 cm used to measure tensile strength and a number of twelve prisms of dimensions 10x10x50 to evaluate the flexural strength. All specimens were immersed at 5% concentration Na2SO4 solution for 2, 4 and 6 months. Durability of Self-Curing Concrete The effect of fire on the mechanical properties of self-curing concrete was investigated. A number of sixty cubes of dimensions 10x10x10 cm used to evaluate compressive strength, a number of forty-eight cylinders of 10x20 cm used to measure tensile strength and a number of forty-eight prisms of dimensions 10x10x50 to evaluate the flexural strength. The studies of fire effect divided into two parts. The first part studied the effect of temperature time at 200o C for different periods (2, 4, 6, 8, and 10 hours) and the effect of storage periods after exposure to the fire. Two storage periods were selected (2 and 4 weeks) these specimens compared to the specimens that tested after (0 week) of exposure to the fire. The second part studied the effect of elevated temperature (400 o C, and 600o C) for constant period (2 hours) compared to the specimens exposed to 200oc for 2 hours. The tests were performed after (0 week) of exposure to the fire.
The effect of chloride on the mechanical properties of reinforced selfcuring concrete was investigated. Test samples are reinforced self-curing concrete beams of dimensions 10x15x100 cm. They immersed at 5% concentration NaCL solution for one and two months using electrical cell to accelerate the corrosion process. The properties, which were taken into consideration in this section of research, were the compressive strength at age of 7, 28 and 56 days. The load deflection behavior of the self-curing reinforced concrete beams was discussed, compressive strain and tensile strain, the cracking and ultimate loads were revealed and the cracking pattern. The important results of this study confirm that The sulfates had a bad effective on the mechanical properties of self-curing concrete as it attack the concrete (in rang of the study). The compressive strength of Self-curing concrete decreased with increase the degree of temperatures. The chloride improved the behavior of reinforced self-curing concrete and the compressive strength of the self-curing concrete at the different ages.