Production of aerated alkali-activated slag pastes and mortars using hydrogen peroxide

Şahin, Murat
Utilization of ground granulated blast furnace slag (GGBFS) through alkali activation for the production of construction materials can provide economic and environmental advantages. In this study, cement-free lightweight composites based on the alkali activation of GGBFS were produced with the incorporation of hydrogen peroxide, and their physical, thermal, and mechanical properties were investigated, under different curing conditions. Various water-to-slag ratios (W/S), hydrogen peroxide contents, and sand-to-slag ratios (Sa/S) were used to explore the expansion mechanism of fresh mixtures and to investigate the apparent density of produced samples. The compressive and flexural strengths and water absorption of sealed-cured pastes and mortars were investigated at room temperature. In addition, the effect of ambient curing and humid-oven curing on the compressive strengths of selected series of pastes and mortars were investigated. Thermal conductivities of aerated pastes were measured. The size and amount of pores were assessed on selected series of aerated pastes and mortars. Aerated pastes and mortars were produced in the apparent density range of 516-1603 kg/m3 and with 0.5-30.0 MPa compressive strength. Thermal conductivities of aerated pastes varied from 0.117-0.206 W/m.K in the dry density range of 480-1098 kg/m3. The use of hydrogen peroxide in the range of 0.25 %-0.75 % (by mass of slag) was sufficient to produce lightweight composites which can be used for insulation and semi-structural purposes in the construction industry.


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Citation Formats
M. Şahin, “Production of aerated alkali-activated slag pastes and mortars using hydrogen peroxide,” Ph.D. - Doctoral Program, Middle East Technical University, 2017.