Effect of source materials, additives on the mechanical properties and durability of fly ash and fly ash-slag geopolymer mortar: A review

Synthesis of fly ash based geopolymer mortar considering different concentrations and combinations of alkaline activator solution

Mechanical properties of geopolymer concrete reinforced with steel and glass fibers with various mineral admixtures

Utilizing natural resources as building materials are not suitable for sustainable development as it will lead to the depletion of natural resources in the future. Hence, the use of waste materials is taken into consideration in the context of the construction industry. In terms of converting waste materials to useful products, industrial wastes of various types such as fly ash, bottom ash and blast furnace slag can be used in geopolymer technology. Considering the demand for producing high mechanical properties of geopolymer, recent innovation has led to the development of pressed geopolymer. It combines the benefit of low alkali activator content and pressure compaction proved that pressing method is featured in a simple process, time-saving, cost-saving as well as facile in large scale production. To bring a better understanding of the pressing method, two types of pressing methods are clarified. Furthermore, few types of waste that can be used as starting materials for geopolymer production are suggested in this chapter. Besides, this chapter also discussed the factors that influence the properties of pressed geopolymer.

Development of Ash-Based and Slag-Based Pressed Geopolymer

Geopolymer is a new development in the world of concrete in which cement is totally replaced by pozzoloanic materials like fly ash and activated by highly alkaline solutions to act as a binder in the concrete mix. For the selection of suitable ingredients of geopolymer concrete to achieve desire strength at required workability, an experimental investigation has been carried out for the gradation of geopolymer concrete and a mix design procedure is proposed on the basis of quantity and fineness of fly ash, quantity of water, grading of fine aggregate, fine to total aggregate ratio. Sodium silicate solution with Na2O = 16.37 %, SiO2 = 34.35 % and H2O = 49.28 % and sodium hydroxide solution having 13M , 10M 15M concentration were obtained throughout the experiment. Water-to-geopolymer binder ratio of 0.40, alkaline solution-to-fly ash ratio of 0.35 and sodium silicate-to-sodium hydroxide ratio of 2.0 by mass were fixed on the basis of workability and cube compressive strength. Workability of geopolymer concrete was measured by flow table apparatus and cubes of 150 mm .side were cast and tested for compressive strength after specified period of oven heating. The temperature of oven heating was maintained at 60 °C for 24 h duration and tested 7 days after heating. It is observed that the results of workability and compressive strength are well match with the required degree of workability and compressive strength. So, proposed method is used to design normal and standard geopolymer concrete.

http://www.ijsrp.org/research-paper-0216/ijsrp-p5061.pdf

Abhishek C. Ayachit

Papers

Mix design of fly-ash based geopolymer concrete