EXPERIMENTAL INVESTIGATION ON FLEXURAL BEHAVIOR OF GEOPOLYMER CONCRETE

Inorganic polymer concrete (geopolymer) is a rising class of cementitious material in which bond is supplanted by flyash, one of the bottomless modern results on earth. Eight trial mixes are prepared for M30 grade concrete with 100% replacement of cement with ASTM class F flyash. In this project, NaOH of 12M and 14M are used as the alkali activator solutions in four different percentages viz., 0.4%, 0.45, 0.50% and 0.55% of flyash. Natural river sand and coarse aggregates of 20 mm maximum size are used for all the geopolymer concrete specimens. The optimum percentage of alkali activator solutions is arrived by conducting the tests for compressive strength, split tensile strength and flexural strength on the geopolymer concrete specimens. From the experimental results, it is observed that there is no significant variation in strength properties of geopolymer concrete mixes when compared to that of the normal concrete. Geopolymer concrete with 0.4% of alkaline solution of 14M is found to be the optimum mix proportion and its compressive strength is improved by 7% than that of conventional concrete specimen. The experimental investigation on the flexural behavior of geopolymer concrete beams are carried out by conducting two point load tests on three beams of size 1000mm × 100mm × 200mm. From the flexural tests, it is observed that there is no significant variation in the flexural behavior of geopolymer and conventional concrete. Therefore geopolymer concrete can be used in the place of conventional concrete with cement and thus provides the solution for both the disposal problem of fly-ash from the thermal industries and pollution threat for the environment due to Carbon-di-oxide emission during the cement production.