ABSTRACT
Concrete is an incredibly versatile and strong material that is essential to a variety of construction projects. However, achieving the right mix and strength can be a delicate process that requires careful attention to detail. One crucial aspect of this process is aggregate grading, which plays a key role in determining the compressive strength of concrete. To better understand the impact of aggregate size on compressive strength, this experiment was conducted with four different aggregate sizes (5 mm, 10 mm, 14 mm, and 20 mm) as well as a control group. The experiment utilized a constant mix of 1:2:4 with a water/cement ratio of 0.6 and involved tests of both workability and compressive strength.
The results of the experiment were illuminating. It was found that workability, as measured by the slump test, increased with larger aggregate size. Specifically, the concrete made from the 5 mm, 10 mm, 14 mm, and 20 mm aggregate sizes had workability (slumps) of 8 mm, 10 mm, 15 mm, and 20.5 mm, respectively. In other words, the larger the aggregate size, the more easily the concrete could be worked with and molded into shape.
In terms of compressive strength, the experiment revealed a clear trend. As the aggregate size increased, so too did the mean compressive strength of the concrete. Specifically, the mean compressive strengths for the 5 mm, 10 mm, 14 mm, and 20 mm aggregate sizes were 21.00 N/mm2, 22.2 N/mm2, 24.1 N/mm2, and 25.9 N/mm² respectively. This suggests that larger aggregates can help to create stronger, more durable concrete. Overall, the experiment provides valuable insights into the role that aggregate grading plays in concrete mixing and strength. By carefully selecting the right aggregate size, builders can achieve the desired balance of workability and compressive strength in their concrete mixes.
