Evaluation of mechanical properties of paver blocks by replacing cement with fly ash and marble waste

Abstract

Paver blocks (PB) play a pivotal role in various construction and infrastructure works providing aesthetically and durable pleasing surfaces for various applications such as pavements, walkways, and driveways. These blocks can be used for heavy vehicle loads instead of low-strength clay bricks and tiles. PB gained focus in the construction industry due to its multi-advantages like high strength, durability, and low maintenance cost. However, due to the usage of cement, its application is limited, which releases a huge amount of carbon dioxide into the ecosystem. Thus, it leads to global warming and climate change. In addition, cement is one of the expensive materials used in PB, which further reduces the interest of the construction industry and end-users of PB. Marble waste as its excessive amount of generation from stones in industry and fly ash as a byproduct from coal combustion immediate opportunities to use these materials and reduce the impact of waste material on the environment. Therefore, this study aims to reduce cement consumption by partially replacing marble waste and fly ash combinedly. The study contributes practically to the use of alternative materials in the construction industry. Three types of samples namely M1 (replacement with marble waste), M2 (replacement with fly ash), and M3 (replacement with both fly ash and marble waste) were used. Various proportions were added as a partial replacement, the replacement varying from 5 to 30%, which was 5%, 10%, 15%, 20%, 25%, and 30%. Statistical analyses were carried out for interpretations of the data. The result concluded that all three mixes achieved their maximum compressive strength on different days of curing. M1-15 and M3-20 mixes achieved maximum compressive strength related to control specimens at 56 days. However, the M2-20 mix achieved maximum compressive strength at 7, 28, and 56 days, The maximum flexural strength was recorded by the M1–15 mix at 7 and 56 days, while the M2–20 and M3–20 mix achieved maximum flexural strength at 7, 28 and 56 days. ANOVA tests by one-way indicate that there is no difference in the mean of compressive strength however, there is a difference in the mean of flexural strength. The Tukey post hoc analysis shows a statistically significant difference between all levels of days of compressive and flexural strength, except for some levels of compressive strength. The correlation test results indicate a positive and strong association between all three mixes.