EXPERIMENTAL EVALUATION OF LOW CALCIUM FLY ASH BASED GEOPOLYMER CONCRETE

摘要

There are many ways to reduce environmental pollution that causes by production of Portland cement and cause by the increasing of waste material. Geopolymer concrete results from the reaction of a source material that is rich in silica and alumina with alkaline liquid. In this experiment low calcium (ASTM Class F) fly ash based Geopolymer is used as the binder, in the replacement of portland cement to produce Geopolymer concrete. The alkaline liquid that been used in geopolymerisation is the combination of sodium hydroxide (NaOH) and sodium metasilicate (Na2Sio2). Fly ash has been collected from Badarpur NTPC plant, New Delhi. In the present study, three (3) series of geopolymer concrete specimens composing molar of sodium hydroxide (NaOH) which is 8M was adopted. There are 9 cube specimens at size 150mm x 150mm x 150mm were prepared. The test specimens were cured at 60 degree in an oven and at ambient condition. The curing time varied from 24 hour to 168 hours (7 days). The result shows that the strength of geopolymer concrete after 24 hour is not superior and after 7 day the compressive strength of Geopolymer concrete is moderate. Therefore further curing period and temperature should be improved.