Comparative study of durability and microstructure properties of concrete made with different grades of Nigerian Portland limestone cement

Abstract

It is now becoming apparent that concrete should not only be strongbut mustalso be durable. It is also believed that understanding the microstructureof theconcrete will help produce strong and durable concrete, and thus enhance innovativeness in concrete application. This paper compares the durability performance and micro structure development of concrete produced with Portland limestone cement (PLC) grades 32.5R and 42.5R. The durability investigation was accomplished through coefficient of water absorption and sorptivity measurements. The scanning electron microscopy (SEM) was used to investigate the microstructure of the concrete samples. The results show that concrete produced with cement grade 42.5R showed higher durability potential than the ones produced with grade 32.5R using 28 days curing period. Similarly, it was also observed that concrete specimens produced with 32.5 Rand with water/cement ratio of 0.40 have better durability index at the later days curing of 90 days in comparison to grade 42.5R concrete specimens. It can be concluded that concrete produced using grade 42.5R cement has potential for better durability performance in relation to concrete produced with 32.5R