Effect of curing conditions on properties of geopolymer mortar

ABSTRACT Ph.D. Thesis EFFECT OF CURING CONDITIONS ON PROPERTIES OF GEOPOLYMER MORTAR Abdoslam Abdallaa ALNKAA Kastamonu University Institute of Sciences Department of Material Science and Engineering Supervisor: Prof. Dr. Hasbi YAPRAK A sustainable environmental approach is one of the most important and decisive factors of today and the production of environmentally friendly products are encouraged by almost all industrial sectors. Geopolymers, which are considered as third generation cement after lime and Portland cement, is considered as an environmentally friendly product as an alternative to Portland cement due to its low CO2 emission and lack of for firing. In addition to reducing CO2 emissions, geopolymers have environmental and economic benefits such as recycling and recycling of industrial waste such as fly ash and YFC. In the study, samples of different sizes were prepared in order to determine the properties of geopolymer mortars consisting of blast furnace slag (YFC), fly ash (UK), waste glass powder (ACT), and sodium hydroxide (SH) and sodium silicate (SS) as an activator. To the mortar samples were performed on steam cure at 85 °C (12 hours) and water cure at 20 ± 2 °C. After curing process, physical properties of samples such as specific gravity, unit weight, water absorption, capillary, drying shrinkage, compressive and flexural strengths of 2, 7, 14, 28 and 90 days, ultrasound test, freezing thaw and sulfate resistance properties were determined. It was observed that steam curing was more effective on the mechanical properties of geopolymer mortars than water curing, MgSO4 had a negative effect on slag and wastevglass powder aded geopolymer mortars and slag and fly ash aded geopolymer mortars were more resistant to MgSO4. When GP mixtures exposed to the effect of MgSO4 for 9 months, it was determined that the compressive strength increased in the case of the UK ratio increased and ACT ratio decreased. Compressive strength increased after 150 freeze-thaw cycles due to the increase of in YFC / UK ratio, because of the increase of the YFC / ACT ratio, compressive strength decreased. Water curing was found to be more effective on freeze-thaw resistance of the samples. Key Words: Fly ash, Slag, Waste glass powder, Geopolymer mortar, Mechanical properties, Durability