STUDY OF THE PHYSICAL, MICROSTRUCTURAL, HYDRAULIC AND MECHANICAL BEHAVIOR OF UNSATURATED SOIL HORIZONS IN RISK AREAS IN BAIXADA SANTISTA-SP

• Grant number: 23/04461-4
• Support Opportunities: Regular Research Grants
• Start date: August 01, 2023
• End date: July 31, 2025
• Field of knowledge: Engineering - Civil Engineering - Geotechnical Engineering
• Principal Investigator: Mariana Ferreira Benessiuti Motta
• Grantee: Mariana Ferreira Benessiuti Motta
• Host Institution: Faculdade de Engenharia (FEG). Universidade Estadual Paulista (UNESP). Campus de Guaratinguetá. Guaratinguetá , SP, Brazil
• Associated researchers: marcio roberto magalhães de andrade

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. 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, aiming to evaluate the physical, microstructural, hydraulic and mechanical characteristics of unsaturated soil profiles in sites monitored by CEMADEN (National Center for Monitoring and Alerts of Natural Disasters) with volumetric water content sensors, through platforms of geotechnical data collections (PCD's), in Baixada Santista-SP. 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's sensors, carry out modeling with the aid of the GeoStudio software to study scenarios and understand the main processes associated with soil behavior in this location, where such a study can serve as a reference in decision making to improve landslides early warning systems. (AU)