Effects of Soil Sulfate Exposure on Surface Concrete Elements in Coastal Residential Buildings

Abstract

This study investigates the effects of soil sulfate exposure on surface concrete elements in resi-dential buildings in Parish on October 18, Canton of Portoviejo, Manabí, addressing a significant gap in local knowledge. From May to October 2023, 20 soil samples were collected and Geo-graphic Information Systems (GIS) were used for exposure mapping. Tests were performed ac-cording to the ASTM D2487 and ASTM C1580 standards to classify soil types and measure sulfate concentrations, following the Ecuadorian Construction Standard (NEC-SE-HM-2015) and ACI 318-19 guidelines. The findings revealed a predominance of clay soils (7 CH and 10 CL) and silt soils (2 MH and 1 ML), with moderate to very severe sulfate concentrations. These concentra-tions were associated with visible damage to the concrete structures, including efflorescence and surface erosion. This study provides a detailed classification map of sulfate exposure and its ef-fects on concrete, offering crucial insights for future construction and repair projects in the re-gion. The results highlight the importance of selecting appropriate materials and employing suitable construction techniques to mitigate sulfate-induced damage in concrete.