الفهرس 
INTRODUCTION AND RESEARCH SIGNIFICANCEOnly 14 pages are availabe for public view
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Abstract
Alkali activated concrete is promising step to decrease pollution. These concretes can be considered as alternative to Portland cement concrete that is one ofthe major reasons of pollution. This thesis deals with two types of these concretes through two phases. The first concrete represents ground granulated blast furnace slag (GGBFS) geopolymer concrete(S-GPC), and the second is lime activated slag concrete (LASC). The first phase includes fresh concrete properties, hardened concrete properties, microstructures, sulphuric acid attack resistance, and corrosion of steel embedded in this S-GPC or S-GPC modified with fly ash (FA) with or without silica fume (SF). The main variables of this phase were: FA content as a replacement of GGBFS (0.0, 10, 20, 30, and 40 %), presence of silica fume (SF) as a replacement of GGBFS (5, and 10%) of the total binder content for slag fly ash silica fume geopolymer concrete, molarity of sodium hydroxide, NaOH, (10, 16, and 18), added water content (7.5, 11, 14, and 20 %), and curing type (thermal, air, and water). The previous variables were studied through 41 concrete mixes. The second phase deals with activation of GGBFS with lime to produce lime activated slag concrete (LASC). Properties of fresh concrete properties, hard concrete properties, and microstructures were studied. The main variables were: lime content (0, 10, 20, and 30% of GGBFS content), added cement content (0, 10, 15, and 20%), presence of gypsum (0, 2, and 4%), cementitious material content, and curing condition. Seventeen concrete mixes were used in this phase. This research studied the slump, slump loss, initial setting time, final setting time, and mechanical properties of S-GPC (compressive strength, splitting tensile strength, modulus of elasticity), also SEM (Scanning electron microscope), and X Ray analysis were included for the two studied phases. For the first phase; concrete cube specimens where submerged in sulphuric acid of PH ranges from 1.5 to 0.6 up to 5 months. Acid resistance of concrete was evaluated through weight loss, compressive strength loss, voids ratio change, absorption, and microstructure tests IV (Scanning electron microscope, and X-Ray). Rate of corrosion and polarization of reinforced concrete specimens were measured as indictors to corrosion resistance of geopolymer concrete. S-GPC yielded rapid stiffening and high slump loss with high mechanical properties compared with fly ash slag geopolymer concrete. The use of silica fume or fly ash or a mix of them with this concrete enhanced workability, decreased rate of slump loss, and delayed setting time. The use of GGBFS geopolymer concrete (S GPC) showed the best sulphuric acid attack and corrosion resistance compared with those containing fly ash and silica fume. 100% GGBFS alkali activated concrete shows the best corrosion resistance. The increase of FA content decreases the different properties used to evaluate durability. Neural network was used to predict guidelines to design mix of S-GPC. Second phase: For LASC without gypsum or cement, the use of 20%lime with 80% GGBFS showed the optimum compressive (20.4MPa), and tensile strength (1.88 MPa). Using 4% gypsum with 80% GGBFS, and 20% lime produced 28 days cube compressive strength of 29 MPa, and splitting tensile strength of 3.25 MPa, which is cheaper than geopolymer concrete activated by NaOH, and Na2SiO3. The addition of 15 % cement content to this concrete increased the 28 days cube compressive strength, and splitting tensile strength to 39.9 MPa, and 4.2 MPa respectively. A theoretical model using neural network and matlab program was prepared. The model ensured good agreement with experimental data. General relations between compressive strength and the main variables affecting compressive strength were adjusted. Approved guides for SGPC mix design is presented.