الفهرس 
Chapter (1) IntroductionOnly 14 pages are availabe for public view
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Abstract
The main objective of this research work is to develop the performance of traditional concrete containing fly ash by using magnetic field treated water. To achieve this objective, this dissertation is divided into two parallel parts: The first part investigates the optimal magnetizing conditions through twenty-one (21) concrete mixtures based on the highest compressive strength result of concrete cubes, to find out the optimum water velocity and discharge and the optimum magnetization duration represented by the number of cycles. In this part, with velocities equal to (0.27, 0.34, 0.46, 0.69 and 1.06) m/s respectively, four-types of concrete mixes were prepared with each velocity with number of cycles equal to (50, 100, 150 and 200) cycles. The results of the first part show that the best increase in compressive strength is achieved with a water velocity of (0.34) m/s, a water discharge of (0.17) lit/s, and a cycle number of (150) cycles, which are the optimum magnetizing conditions. The second part intends to evaluate the influence of magnetic field treated water prepared at the optimum magnetizing condition on fresh and hardened properties of concrete. To achieve this target, a total of eighteen (18) concrete mixtures were prepared with two types of water (Tap water, Magnetized water), three replacement percentages of fly ash (0, 10, 20)% and three doses of super-plasticizer (0, 1, 2)% by weight of cementitious materials. The mechanical properties were determined by performing the compressive strength test, the tensile strength test, and the flexural strength test. The physical properties were determined by measuring the rebound number and the ultrasonic pulse velocity. Furthermore, the microstructure of cement paste prepared with and without magnetized water was investigated using a scanning electron microscope (SEM), to verify the effect of magnetized water on the morphology and hydration products of cement paste and to identify the factors contributing to improving the mechanical characteristics of concrete incorporating magnetized water. It seems apparent from the results obtained that the mechanical properties and physical properties of concrete samples prepared with magnetized water are higher than those prepared with ordinary tap water at all curing ages.