THE DIRECT STRENGTH OF GEOPOLYMER CONCRETE

ABSTRACT

This body of work documents the investigative study into the direct strength properties of geopolymer concrete. It focuses on comparing the nominal strength properties of geopolymer concrete, an innovation, to those of the more standard, usual Portland cement concrete, recording where it exceeds, falls short or is equivalent. To be clear, it compares the compressive, tensile and flexural strengths of geopolymer concrete to those of ordinary Portland cement concrete by laboratory testing of both specimens subjected to the exact same conditions. At this juncture, it is important to note that metakaolin (a calcined form of kaolin clay when it is subjected to temperatures above 800℃) is the geopolymeric material of choice due to its ready availability. Hitherto, batches of kaolin have been calcined successfully, and preliminary tests have proven that the resulting metakaolin specimens are reactive when exposed to alkaline activators; also, that metakaolin-based geopolymer concrete can greatly exceed the strengths of cement concrete based on a 49MPa compressive test result after 7 days.