Paper Title
Effect of Naoh Concentrations and Curing Temperatures on Mechanical Properties of Geopolymer Pastes Produced From Fly Ash And Elaziğ Ferrochrome Slag

Abstract
The effective researches are required for the purpose of minimize environmental pollution due to accumulation of industrial wastes such as fly ash (FA) and ferrochrome slag. The disposal, removal and storage of by-products which are produced apart from the main product is a big problem. In this experimental study, it was attempted to investigate effect of different NaOH concentrations and curing temperatures on mechanical properties of FA and Elazığ ferrochrome slag (EFS) based geopolymer pastes. FA was obtained from Iskenderun Iron & Steel Plant and EFS was obtained from Elazığ Ferrochrome Plant. The raw materials were mixed at equal rate (50% ). Liquid/binder ratio was determined as 0.36 experimentally. NaOH concentration were selected as 8, 10, 12, 14 and 16M. After casting, all samples were cured at 50, 100, 150°C and laboratory conditions for 72h. For each sample produced using this different parameters, 3, 7 and 28-day compressive strengths were tested. In addition, ultrasonic pulse velocity (UPV) values were obtained. When considering compressive strength results, it was observed that obtained values increased from 0 to 82.5MPa with increasing concentration and curing temperatures. Overall results indicated that different NaOH concentration and curing temperatures have a huge impact on compressive strength and UPV values of geopolymer pastes. The experimental findings have also showed that the usage of FA and EFS together as an alternative binding material was advantaged. Keywords - Geopolymer paste, fly ash, ferrochrome slag, compressive strength