Typical geotechnical profiles of the main soil deposits found in the Maceio city, Alagoas, from SPT boreholes

Abstract

This work had as objective to carry out the construction of typical soil profiles of the main existing deposits in the city of Maceio from a database of SPT boreholes, built in GIS environment. In total, 1,686 records of drilling were specialized in sediments of the Barreiras Formation, Coastal Deposits, and lagoons-river, presenting the most frequent characteristics, exemplified through representative profiles. The Barreiras Formation, which covers about 75% of the urban area of the city, presented profiles with a predominance of clayey, without water level records. The deposits lagoons-river, located in the vicinity of Mundaú lagoon, were characterized by the significant presence of soft and organic clays, sometimes peat, it can reach large thicknesses and with the water table rising in certain regions. In the coastal plain, where the highest vertical construction indices in the city are concentrated, it presented an area with a predominance of fine to medium sand, with or without silt, and a water table varying between 1,00 m and 5,00 m. The analysis also allowed for the identification and mapping of the occurrence of limestone rock, sandstone rock, soft and organic clay rocks in the coastal plain, presenting a typical profile of their occurrence, helping to understand the geotechnical behavior of these materials in the studied region.