FLOW AND STRENGTH PERFORMANCE OF GEOPOLYMER MORTAR PARTIALLY REPLACED WITH SUB-SURFACE ROCK POWDER

Geopolymer is an aluminosilicate compound produced as a result of inorganic polymerization. In the present study the use of geopolymers as binder material in mortar where, fine aggregate was partially replaced with subsurface rock powder obtained from depths of 200ft, 400ft and 600ft, was tested. The alkali activator used in the present study was 10M Sodium hydroxide (NaOH) solution. The experiments were conducted on fly ash and GGBS (1:1) based geopolymer mortar by varying the ratios of fine aggregate and sub-surface rock powder. The ratio of alkaline liquid (10M NaOH solution) to geopolymer was fixed as 0.1. The admixture Fosroc auramix V200, whose percentage was fixed as 1.2% determined by the marsh cone analysis test, was used for improving the workability of the mortar. The test specimens were ambient cured. The results showed the compressive strength was highest for the GPM 600 60 40 at 16.4 N/mm2 and lowest for GPM 200 0 100 at 6.31N/mm2 . The general pattern showed that there was an increase in the compressive strength from 7 days to 28 days of curing. During the 7 days testing GPM 200 showed higher compressive strength but after 28 days of curing GPM 600 had higher compressive strength.