Effects of curing time on compressive strength of concrete

Abstract

The effects of curing time on the strength of M20 concrete grade is investigated in this study. The compressive strength development for non-cured cubes, curing period of 7, 14, 21, and 28 days under room temperature using Portland Pozzolana Cement (PPC) has been investigated. From the experimental observation, it is found that in general, the compressive strength increases with age of concrete irrespective of the curing and its duration. The test results shows that 7 days continuous curing cubes achieved 19.04 N/mm² (96 %) of the target strength at end of 15 days. It is obvious that it will achieve its target strength at the end of 28 days. The compressive strength of 14 days continuous curing cubes achieved 20.89 N/mm² at end of 22 days.  The variation in compressive strength of concrete after 21 days of continuous curing doesn’t affects much in achieving its target strength. The minimum of 7 days of continuous curing duration is necessary to gain its target strength of Portland Pozzolana Cement (PPC) concrete works. At the early ages as well as at later ages, it is essential have adequate curing for the development of strength for PCC concrete. It is also observed that under the draying ambient conditions, potential development of strength is reduced for PPC concrete.