الفهرس 
CHAPTER (1): INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
Millions of tons of fresh water are used annually in construction of concrete around the world. Decline of fresh water on earth present an environmental issue. Search for other alternatives to water for use in mixing and curing of concrete is essential. At present, many cities are facing the problem of freshwater shortage. According to the report of the Organization for Economic Cooperation & the Development (OECD), some countries such as Japan, Indonesia and others, inhabited by many people face difficult. Consumption of fresh water is large. Transfer of fresh water and materials in concrete industry leads to higher cost. Therefore, it is necessary to find other alternatives to fresh water. For example, if the use of seawater is allowed in concrete industry, it will be economical and comfortable, although most concrete codes do not allow the use of seawater.
Seawater is a complex solution of salts and dissolved gases. The average salt concentration of seawater is about 3.5% and it varies from sea to sea according to geological location. The primary chemical constituents of seawater are ions of chloride, sodium, magnesium, calcium and potassium. The concentration of major salt constituents of seawater are given in weight % of salt as 78%NaCl, 10.5% MgCl2, 5% MgSO4, 3.9% CaSO4, 2.3% K2SO4, and 0.3% KBr [1].
It evident from above that sodium chloride is by far the predominant salt component of seawater; NaCl and MgCl total 88.5%of the entire salt content [1].1.2 The Thesis Objective
The significance of the provided research is that it provides an alternative to fresh water, since the world suffers from a decline for potable water existing on the earth’s surface, and the most readily available alternative is seawater. As a result, saltwater was employed in mixing and curing without any additives, resulting in concrete disintegration after 28 days. Mineral admixtures were utilized to mitigate the harmful effects of saltwater, and the findings revealed an improvement in the characteristics of concrete.
1.3 Thesis Outline
This thesis contains five chapters. They are as follows:-
Chapter one: Introduction to concrete manufacture and the aim of the work.
Chapter two: Collection, description, analysis and discussion of the previous studies in the field of research. It also illustrates application used to manufacture seawater concrete.
Chapter three: Contains the experimental program and detailed explanation of the laboratory experiments conducted to produce concrete using sea water and material characterization.
Chapter four: Illustrates the results and discussion of tests of the experimental program.
Chapter five: Elucidates the conclusion of the research, recommendations, and further studies.
Conclusion:
1- Mineral admixtures have a significant effect on the workability of concrete for seawater mixtures. This appeared in the mixture of MK 3% with 30% FA or 40% FA.
2- The compressive strength of seawater mixture increased by 9.69% at 7 days compared to fresh water mixture. At the age of 180 days, compressive strength of seawater mixture decreased by 29.2%.
3- Mineral admixtures enhanced the compressive strength of seawater mixtures at the age of 90 days. Whereas, the compressive strength recorded an increase of 57% for the 7%MK30%FA mixture compared to the compressive strength of seawater mixture without admixtures.
Fresh water mixtures with mineral admixtures recorded an enhancement in compressive strength, and this was represented in the mixture of 5% MK40%FA by 58% and this is compared to fresh water mixture.
4- The tensile strength of the seawater mixture improved by 13.7% at the age of 28 days compared to the fresh mixture. At 180 days of age, tensile strength in seawater mixture decreased by 27.5%.
5- The flexural strength of the seawater mixture increased by 22.7% at the age of 28 days, compared to fresh water mixture. At 180 days of age, the flexural strength in the seawater mixture decreased by 44.4%.