Effects of Snail Shell Waste on Compressive Strength of Concrete with Partial Cement and Fine Aggregate Replacement

Abstract

The concrete industry is under increasing pressure to reduce cement consumption and natural aggregate exploitation to enhance environmental sustainability. In Leupung District, Aceh Besar Regency, Indonesia, the consumption of black snail as a traditional local food, rooted in coastal community local wisdom, generates significant shell waste that remains largely underutilized. While previous studies have extensively examined other biogenic wastes, the use of snail shell waste (SSW) as a partial replacement for cement and fine aggregate has received limited attention. This study proposes an innovative integration of local wisdom with modern concrete technology by employing SSW as a dual substitution material. The objective was to evaluate the compressive strength performance of concrete incorporating snail shell waste at replacement levels of 0%, 5%, 10%, and 15%, targeting a design strength of 17 MPa. Compressive strength tests were conducted in accordance with ASTM and ACI standards. The results showed compressive strengths of 21.98 MPa for the control mix and 19.23 MPa, 17.86 MPa, and 17.53 MPa for the 5%, 10%, and 15% mixtures, respectively. Regression analysis revealed a strong negative linear relationship (y = −0.2948x + 21.361; R² = 0.8808) between replacement level and compressive strength. Although strength decreased with increasing substitution, all mixtures met the target concrete strength, indicating that SSW derived from local wisdom practices is suitable for application in non-structural concrete and contributes to sustainable waste utilization.

Keywords: cement, compressive strength, concrete, fine aggregate, snail shell.