Durability and mechanical properties of cement partially replaced by seashells

Melendez J.; Huamancusi E.; Eyzaguirre C. · Proceedings of the LACCEI international Multi-conference for Engineering, Education and Technology (2025) · DOI: 10.18687/laccei2025.1.1.2241

Resumen

Concrete is one of the most widely used materials in the construction industry, playing a crucial role in the development of new infrastructure essential to society. However, its excessive use generates significant amounts of CO2 worldwide. In this context, new research has emerged proposing a more eco-friendly and sustainable concrete industry. The development of an ecological concrete incorporating recycled seashell powder aims to repurpose organic waste and contribute to environmental conservation. This study investigates the compressive strength development of ecological concrete that includes seashell powder as a partial replacement for cement. The objective is to evaluate the impact of seashell powder on the mechanical performance of concrete, with a particular focus on the compressive strength achieved at 28 days. In this research, cement was replaced with seashell powder at substitution rates of 4%, 8%, and 12%, based on previous findings suggesting potential benefits for strength development. Concrete specimens were prepared and tested at different curing intervals (7, 14, 21, and 28 days) to monitor the evolution of compressive strength over time. The results showed a positive effect on both early-age and final compressive strength, demonstrating the viability of seashell powder as a sustainable alternative material in concrete mixtures. It was confirmed that compressive strength increased when the replacement rate was 4% and 8% at 28 days. However, a 12% replacement resulted in lower compressive strength at 28 days compared to the control mix. In conclusion, this study provides valuable insights into the potential of utilizing waste seashells to reduce cement consumption, contributing to environmental sustainability in the construction industry. Based on the findings, this research recommends replacing cement with seashell powder at an optimal rate of 8% by weight.

Instituciones: Universidad Peruana de Ciencias Aplicadas