الفهرس 
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Abstract
This research aims to elucidate the effect of Local Chemically Activated Blast Furnace Slag on Chloride Ingress in Hardened Mortar. The used SLAG replaced OPC by 10 and 20%, three different types of alkali-based chemical activators (sodium silicate, sodium carbonate and lithium hydroxide) were used with the OPC mix containing 20%SLAG. Chloride ingress was assessed by measuring Chloride Penetration Test, as a function of depth (chloride profile). To broaden the understanding, compressive strength, sorptivity TGA, capillary porosity and MIP were conducted. The results reveal that, chloride ingress resistance increased with increasing local SLAG replacement level. However this resistance can be enhanced by using chemical activator. The used chemical activators with 20%SLAG mix improve its microstructure. The use of lithium hydroxide as a chemical activator improves chloride ingress resistance for 20%SLAG mix higher than the other used activators.
Nine OPC mortar mixes made with various local slag contents (10and 20%, by mass of OPC) with various chemical activators (lithium hydroxide, sodium silicate and sodium carbonate) by content of 1 and 3% by weight of cement were prepared to study the impacts of inactivated and activated local slag on: 1) the fresh properties (flowability, rate of flow loss and rheology), using mortar flow table apparatus, 2) the mechanical properties (compressive) and 3) the mass transport properties (sorptivity , total chloride profile and rapid chloride penetration)
Nine OPC paste mixes made with different slag contents (10 and 20%, by mass of OPC) with various chemical activators (lithium hydroxide, sodium silicate and sodium carbonate) were prepared to study the impacts of chemical activation and content of slag on the microstructure characteristics (hydration products and pore structure) of OPC matrix, by means of thermo-gravimetric analysis, de-sorption and mercury intrusion porosimetry approaches. The main findings of this investigation were as follows:
1. Chloride ingress resistance decreased with increasing local SLAG replacement level. 2. Inclusion of local SLAG by 10% as a partial replacement in OPC matrix has a slight effect on its chloride penetration resistance. However, it has a notable effect on compressive strength and paste microstructure. 3. Increasing local SLAG content to 20 % in OPC matrix decrease its chloride ingress resistance, compressive strength and adversely affect paste microstructure. 4. The used chemical activators (sodium carbonate, sodium silicate and lithium hydroxide) with 20%SLAG mix improve chloride penetration resistance and the paste microstructure in terms of hydration products and decreasing the porosity. 5. The use of lithium hydroxide as a chemical activator improves chloride ingress resistance, compressive strength and the paste microstructure for 20%SLAG mix higher than the other used activators (sodium carbonate and sodium silicate). Key Words: Slag, Activation, Fresh properties, porosimetry, sorptivity, Mass transport properties, Rheology, Microstructure, Durability.