Geological and Geotechnical Characterization of Soils from the Barreiras Formation in a Subarea of Study in Maceio, Alagoas State, Brazil

摘要

The Barreiras Formation comprises approximately 75 of the urban area of Maceio-Alagoas, which has a vast number of steep densely occupied slopes, located in embedded valleys called "grotas" where erosive processes cause a high risk of landslides. Despite the homogeneity of the local geology, the Barreiras Formation still presents few studies that provide geological/geotechnical information, and it is under these perspectives that this article is developed, part of a research carried out by the Federal University of Pernambuco through the Geotechnical Engineering Group for Slopes, Plains and Disasters. The geological/geotechnical characterization was carried out through the construction of a database with 474 SPT boreholes, located in a subarea of study in the city of Maceio, where it was possible to carry out a geostatistical evaluation of the penetration resistance values (Nspt) using the ordinary kriging method and the establishment of engineering geological units. A geotechnical detail study was carried out on a slope (Grota da Moenda) inserted in the studied subarea, which involved field investigations by means of the execution of SPT borehole and collection of undisturbed samples, while laboratory investigations provided information regarding the physical and mechanics of the soil through permeability (Tri-flex) tests, suction, double oedometer, direct shear and triaxial CID tests. The geotechnical parameters obtained in this research together with the probabilistic maps are of great importance in learning about the behavior of the soils in the investigated place, presenting initial parameters that could help in several engineering projects.