Quality assessment of SCGPC using ultra-sonic pulse velocity at high temperature

Abstract

This paper presents the effect of high temperature on compressive strength and ultra-sonic pulse velocity of self compacting geopolymer concrete (SCGPC) mixes with varying molarities viz., 8M, 10M and 12M. At different ages, the specimens were kept at a high temperature (100, 200, 400, 600 and 800oC) for 2 hours and then testing of the specimens was carried out. Prior to compressive strength of test specimens, ultra-sonic pulse velocity (UPV) test was performed after 7, 28 and 56 days of curing. From the results, it is revealed that the compressive strength and UPV results of SCGPC were decreased with the increase in temperature from 1000C to 8000C in all curing periods. Finally, it is concluded that the significant decrement in compressive strength and UPV up to 8000C is mainly due to continuous moisture loss from the specimens and increase in the average pore size, which produce the lower strength and pulse velocity of the concrete.