Investigation of alkali activated electrical arc furnace slag concrete properties

In this study, Electric Arc Furnace Slag (EAFS), which gathered as a by-product in Osmaniye iron and steel mills belonging to TOSCELIK INC., is activated by alkalis and its effects on concrete properties (compressive and tensile splitting strengths, abrasion resistance, ultrasonic pulse velocity, capillary water absorption, water absorption, water permeability depth under pressure, gas and chloride ion permeability) are investigated. For this purpose, water/binder and cement dosage were kept constant at 0.4 and 400 kg/m3, respectively. EAFS has been replaced by 10%, 20%, 30% by weight instead of cement. The mixtures were prepared with three different concentrations of sodium (4%, 6%, 8%). In all mixtures except the control sample which does not contain EAFS, the silicate modulus are 1 and 2. The 18 different mixtures produced in total are subjected to 28 days of standard cure at the end of which they were removed from water and subjected to compressive strength, tensile splitting strength, ultrasonic pulse velocity, schimidt hammer, abrasion resistance, capillary water absorption, water absorption, water permeability depth under pressure, gas and chloride ion permeability tests. When the test results are examined, it is seen that Sodium Silicate-Sodium Hydroxide mixture is effective in activating EAFS and 4% sodium concentration is enough for that purpose. It has been determined that EAFS activated with an activator with a concentration of 4% sodium, especially when used in 20% by weight rather than cement, affects positively the parameters such as strength, abrasion resistance,water absorption and permeability of the concrete.