الفهرس 
Introduction
Chemical interactionOnly 14 pages are availabe for public view
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Abstract
The objective of this study is to improve the efficiency of cement in concrete mix by mechanical means. Lose Angeles Machine was used to grind and rotate the constituents of mortar. The thesis aims also to clarify the economical benefits and the technical advantages of using this new technique for producing superplasticized mortar and concrete. There are three proposed techniques for producing superplasticized mortar and concrete. Grinding cement, sand, powdered superplasticizer, and silica fume is most effective than other techniques. Four cycles? number were used to produce superplasticized cement; 250, 500, 750, and 1000 cycles. Two types of superplasticizer (NSF) were used; liquid and powdered. The results show that; grinding the mixture enhances fresh and hardened properties of mortar and concrete. Grinding the mixture for 500 cycles (17 minutes) is effective than other numbers. It increases compressive strength at 1 and 7 days by about 25% and 19% for mortar respectively, and by about 18% and 19% for concrete at 1 and 28 days respectively. Grinding superplasticizer powder enhances fresh and hardened properties of mortar and concrete more than adding it to mixer or adding it as a liquid. This technique has many benefits such as; saving cement, saving labor, high quality control, and enhancing permeability and durability of concrete. There are many fields of application of this new technique such as; normal constructions, locations not easily accessible by ordinary concreting techniques, repair, patching, thin coating, grouting for deep oil wells, for producing early and high strength concrete, and for small projects when ready mix supply is not feasible