الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
The global warming and the associated climatic changes have recently become a major concern due to its direct adverse effect on the earth’s environment. Carbon dioxide is the main source of this phenomenon. Researchers have found that the production of one ton of Portland cement liberates about one ton of CO2 to the atmosphere. Therefore, new materials should be discovered to overcome this phenomenon. Alkali activated inorganic materials ”Geopolymer” attracted a great challenge as a new environment friendly engineering materials. This new materials reduce CO2 emission up to 80-90% [1], and it has a desirable properties such as; early strength, low permeability, excellent resistance to chemical attack [2]. Although alkali activated inorganic materials using slag as raw material reduce CO2 emission [3], it has a fast solidification property, highly drying shrinkage which lead to formation of microcracks. In order to improve several properties of alkali activated slag ”slag geopolymer” (GS) such as brittle behavior and their low flexural strength, organic polymer materials can be incorporated in GS. Another common drawback of GS is a high shrinkage during curing process and fast setting, these properties can be reduced by adding filler materials such as sand, gypsum, fly ash or other mineral materials. The main objective of this research is to study the microstructure, physical and mechanical properties of GS and focus on a new class of GS by hybrid combination of inorganic and organic materials. In this research, Styrene butadiene rubber (SBR) and Acrylic ester (AE) are used as common types of organic polymer materials ”Latex” in GS. The percentage of these types varied from 5% to 15% by weight of binder to investigate the optimum content of organic polymers. Another type of binder such as fly ash or combination of fly ash and slag by ratio 4:1 are studied to make a comparison between GS and new class of alkali activated inorganic materials modified with latex. Many factors which has a great effect of GS properties such as curing temperature, ratio between sodium hydroxide and sodium silicate in activator solution, thus in this research two curing temperature 30 and 600C and the ratio of Na2SiO3/NaOH is 1:1 or 2.5:1 are studied. This research is divided into three parts. Firstly is the study of fresh alkali activated inorganic materials mortar properties; consistency and setting properties. Physical properties such as water absorption, porosity, and drying shrinkage are determined. Secondly is the study of hardened alkali activated inorganic materials mortar properties; compressive strength, and flexural strength are investigated. Micro structure and scanning electron microscopic analysis ”SEM” is evaluated for GS and other GS modified with 5% latex which exhibit the superior performance in alkali activated inorganic materials properties. Final part of this research focus on using this new class of GS as surface coating materials for concrete surface or as coating on steel reinforcement bars. The results showed that the use of latex increased the setting time and improved the mechanical and physical properties of alkali activated inorganic materials mortar and the best results were obtained by the use of Styrene butadiene rubber (SBR) with 5% ratio. Higher curing temperature showed a significant decrease in the mechanical properties and an increase in the physical properties of alkali activated slag mortar (GS), alkali activated fly ash blended with slag mortar (GFS), GS and GFS modified with latex, while the higher curing temperature for alkali activated fly ash mortar (GF) and GF modified with latex gives better results in all the properties as the high temperatures increase the reactivity of fly ash which leads to improve the properties. Moreover, the increase in solution ratio has enhanced the mechanical and physical properties of alkali activated inorganic materials mortar while, the mechanical and physical properties of alkali activated inorganic materials mortar modified with latex showed better results with solution ratio of 1:1 during the use of Styrene butadiene rubber (SBR) with 5% ratio. In addition the results of using alkali activated slag (AAS) as a concrete surface coating showed a slightly reduction of water penetration depth due to the higher shrinkage of AAS, while using AAS as a steel surface coating presented a significant reduction on Icorr and corrosion rate compared to uncoated steel specimens. By comparing AAS with the most common steel coating materials ”Zinc rich” it exhibits almost the same protective behavior.