EVALUATION OF PHYSICAL, MICROSTRUCTURAL, HYDRAULIC AND MECHANICAL PROPERTIES OF AN UNSATURATED SOIL PROFILE IN THE MUNICIPALITY OF PRAIA GRANDE-SP

• Grant number: 23/13865-1
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: January 01, 2024
• End date: December 31, 2024
• Field of knowledge: Engineering - Civil Engineering - Geotechnical Engineering
• Principal Investigator: Mariana Ferreira Benessiuti Motta
• Grantee: Vinícius Samahá Salles
• Host Institution: Faculdade de Engenharia (FEG). Universidade Estadual Paulista (UNESP). Campus de Guaratinguetá. Guaratinguetá , SP, Brazil

Abstract

Landslides are natural phenomena, but anthropic action can facilitate and accelerate this process. During heavy rains, common in Brazil, the situation becomes worrying and there is a greater probability of occurrence of such disasters, since the soil is in its most critical situation, with a high degree of saturation. Added to this, it is known that in tropical areas, soil formation processes are differentiated due to the more pronounced action of chemical weathering, which is expressed by the great thickness of residual soils, in contrast to regions with a temperate climate, where these soils they are not very thick. Therefore, understanding the behavior of water in a given soil is essential for carrying out effective risk monitoring. In this scope, this project is proposed, linked to the FAPESP project already approved process nº 2023/04461-4, aiming to evaluate the physical, microstructural, hydraulic and mechanical characteristics of an unsaturated soil profile in the Jardim Alice neighborhood, Praia Grande-SP, monitored by CEMADEN (National Center for Natural Disaster Monitoring and Alerts) with volumetric water content sensors, through a geotechnical data collection platform (PCD). The main objective is to characterize soil horizons in order to determine risk moisture ranges, thus ensuring greater refinement in alert emissions for the location. For this purpose, deformed and undisturbed samples of the soils in question will be collected to carry out tests in the laboratory, such as grain size distribution, limit index, permeability tests, retention curves and mercury porosimetry. In addition, in order to complement the hydraulic and mechanical characterization in situ, tests will be carried out with the Guelph permeameter and with the DPL (Light Dynamic Penetrometer), at different depths along the profile, to investigate the phenomena of infiltration and percolation of water in the different identified horizons. With this, it is intended to correlate field and laboratory data with the PCD sensors, aiming to understand the main processes associated with soil behavior in this location, where such a study could serve as a reference in decision-making to improve early warning systems.