Influence of water retention characteristics and suction in the electrical resistivity of tropical soils

• Grant number: 13/01215-0
• Support Opportunities: Scholarships in Brazil - Master
• Effective date (Start): October 01, 2013
• Effective date (End): February 28, 2014
• Field of knowledge: Engineering - Civil Engineering - Geotechnical Engineering
• Principal Investigator: Anna Silvia Palcheco Peixoto
• Grantee: Luciana Garcia Campos
• Host Institution: Faculdade de Engenharia (FE). Universidade Estadual Paulista (UNESP). Campus de Bauru. Bauru , SP, Brazil

Abstract

The studies of modern techniques in geotechnical investigation have been improving each year in order to obtain practical and faster results with higher precision. The electrical resistivity is gaining attention due to their environmental appeal, since the obtainment of this measure happens through the imposition of a electrical current flow in a given material. But the interpretation of results in tropical soil is hampered by the variables involved, such as non-saturation and clay.Through the measure of the resistivity is possible to detect the presence or if the concentration of certain substances in the water table are above a certain benchmark. At areas where benchmarks are extrapolated, it's possible to make a additional evaluation by collecting, at discrete depths, samples of groundwater, providing a quick and economic way of performing geo-environmental characterizations of field.They were developed equipment and methodologies of laboratory tests (Supported by FAPESP, 07/06085-7) to obtain resistivity controlling the intervening factors, such as moisture content, compaction, porosity and saturation degree, thereby providing subsidies for a more accurate analysis to the field trials.In that manner, this master's project intends the development of a study to verify the influences that suction present in unsaturated soils have on the values of resistivity / conductivity. The analyzes will include both trajectories, Wetting and Drying, of water retention curves, that represent the flow of water in the soil during the year, as the wet and dry seasons.This study gains importance in regions of arid and tropical climate, where soils have as main characteristic low humidity near to the surface, having the possibility of undergoing alternate cycles of wetting and drying, and thus, constantly changing the values of suction.

Academic Publications

(References retrieved automatically from State of São Paulo Research Institutions)

CAMPOS, Luciana Garcia. Variation of electrical resistivity for three unsaturated soils. 2015. Master's Dissertation - Universidade Estadual Paulista (Unesp). Faculdade de Engenharia. Bauru Bauru.