Uniaxial compression strength and unit weight of a concrete f'c=210 kg/cm2 when replacing 7.5%, 12.5% and 22.5% of thick aggregate with expanded clay

Nair Castro Torres Y.; Miguel Angel M.-M.; Roberto Mosqueira Ramírez H. · Proceedings of the LACCEI international Multi-conference for Engineering, Education and Technology (2024) · DOI: 10.18687/laccei2024.1.1.282

Resumen

In this investigation, it was determined how much influence replacing the coarse aggregate with expanded clay in 7.5%, 12.5% and 22.5%, influences the compressive strength and unit weight of a concrete of f'c=210 kg/cm2. The results were evaluated by comparing the standard sample made with river aggregates with the samples made by replacing the coarse aggregate with expanded clay. Uniaxial compressive strength was evaluated at ages 7, 14 and 28 days and unit weight in fresh and hardened state across 6”x12” specimens. The research seeks to obtain a structural concrete that meets the technical resistance standards, but reducing its weight, without reaching a lightweight concrete that modifies its properties. Well, by reducing the weight of the structure it allows us to have structures with smaller dimensions of its elements and acting forces, also reducing the amount of materials used and the cost of the structure. According to the results of the research, it is concluded that the unit weight in the fresh state decreases by 1.75%, 3.20% and 4.54%, respectively. And the unit weight in the hardened state after 28 days decreases by 2.89%, 3.91% and 4.91%, respectively. Likewise, the compressive strength at 28 days decreases by 6.66%, 12.34% and 14.36%, with respect to the standard sample, obtaining for all cases a structural concrete with a resistance greater than 210 kg/cm2 and an average unit weight of 2200. kg/m3. These results indicate that the use of expanded clay can be viable by reducing the weight of the concrete, obtaining resistance greater than that stipulated in the Peruvian standard for structural concrete.

Instituciones: Universidad Nacional de Cajamarca