Implementation of hydrated lime derived from scallop shell waste as mineral filler in Stone Mastic Asphalt (SMA) mixtures

Meza F.; Chávez A.; Rodríguez W.; Torres T. · Construction and Building Materials (2025) · DOI: 10.1016/j.conbuildmat.2025.144193

Resumen

Scallop shells represent a by-product of the Peruvian aquaculture industry that currently lacks adequate management strategies, with no effective measures implemented to mitigate the environmental impacts associated with their disposal. This situation is particularly critical given that Peru is among the leading exporters of scallops worldwide, which results in the continuous generation of substantial shell waste. To address this challenge, the potential valorization of scallop shell waste through its transformation into hydrated lime is explored, thereby reducing its environmental burden and promoting sustainable waste management practices. This study assesses the feasibility of replacing commercial hydrated lime (HL) with hydrated lime derived from scallop shells (SSHL), a by-product of the Peruvian aquaculture industry, as a mineral filler in Stone Mastic Asphalt (SMA) mixtures. Chemical analyses using FTIR, SEM, XRD, and XRF techniques were conducted to compare the purity and structural similarity of both materials. In this study, SMA mixtures were modified with 0.30 % fibre and 2.5 % mineral filler by total mixture weight and evaluated through volumetric and mechanical tests. Standardised laboratory methods were employed, including volumetric properties, draindown (Schellenberg) test, stiffness modulus, moisture damage, permanent deformation (Hamburg wheel tracking), and fatigue resistance (IDEAL-CT). The results indicate that SSHL meets volumetric requirements and exhibits satisfactory mechanical performance, comparable to that of commercial hydrated lime. Therefore, SSHL emerges as a sustainable and technically viable alternative for use as a mineral filler in SMA mixtures, contributing to aquaculture waste valorisation and enhancing asphalt pavement performance within the Peruvian context.

Instituciones: Universidad Peruana de Ciencias Aplicadas; Universidad San Ignacio de Loyola