Seismic DMT for site characterization of tropical soils

• Grant number: 15/17260-0
• Support Opportunities: Regular Research Grants
• Duration: November 01, 2015 - October 31, 2017
• Field of knowledge: Engineering - Civil Engineering - Geotechnical Engineering
• Principal Investigator: Heraldo Luiz Giacheti
• Grantee: Heraldo Luiz Giacheti
• Host Institution: Faculdade de Engenharia (FE). Universidade Estadual Paulista (UNESP). Campus de Bauru. Bauru , SP, Brazil

Abstract

The geomechanical behavior of an unsaturated tropical soil has been highlighted in the geotechnical community, not only for implantation of current civil engineering works, but also in the environmental area. Unsaturated tropical soil profiles have a cohesive-frictional behavior, where factors such as macro and microstructure, cementing, nonlinearity of stiffness, anisotropy, genesis and disintegration show greater influence on their behavior than the stress history. The initial stage of geotechnical projects starts with the site investigation. It encompasses the stratigraphical profile and the most appropriate geo-mechanical parameters required for the project. Combined techniques, so-called hybrids tests, have been suggested as current approach to meet all the needs of a proper non-textbook site characterization program. Among several in situ test techniques, the Seismic Dilatometer (SDMT) test has been highlighted, however it has little used in Brazil yet. In this test, besides the definition of stratigraphical profile and estimative of geo-mechanical parameters, it is possible to determine the maximum shear modulus (Go) from the measuring of the shear wave velocity propagation through the soil mass. This research project intends to study the behavior of two typical tropical soils profiles by using the SDMT test. These profiles occur at the experimental research sites of Unesp-Bauru and USP-São Carlos, where several researches have been carried out and a large amount of in situ and laboratory data are available. The main objectives of this research are: to achieve a better site characterization of tropical soils integrating different in situ testing data, to assess the applicability of available correlations presented on the literature to estimate geo-mechanical parameters, to study the Go/MDMT e Go/ED ratios to identify layers with different soil behavior at the studied profiles, and to propose modifications or adjustments in the correlations to be used in tropical soils. Finally, this research will contribute for a better understanding of the unsaturated tropical soils behavior, since they cannot be properly assessed by means of models and correlations developed by the Classical Soil Mechanics. (AU)

Scientific publications

(7)

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

SILVA, N. M.; ROCHA, B. P.; GIACHETI, H. L.. Prediction of Load-Settlement Curves by the DMT in an Unsaturated Tropical Soil Site. SOILS AND ROCKS, v. 42, n. 3, p. 351-361, SEP-DEC 2019. (15/17260-0)

BRENO PADOVEZI ROCHA; HERALDO LUIZ GIACHETI. Site characterization of a tropical soil by in situ tests. DYNA-COLOMBIA, v. 85, n. 206, p. 211-219, 2018-09-00. (11/09031-0, 15/17260-0, 14/23767-8)

GIACHETI, HERALDO LUIZ; BEZERRA, RENAN CRAVERA; ROCHA, BRENO PADOVEZI; RODRIGUES, ROGER AUGUSTO. Seasonal influence on cone penetration test: An unsaturated soil site example. JOURNAL OF ROCK MECHANICS AND GEOTECHNICAL ENGINEERING, v. 11, n. 2, p. 361-368, APR 2019. (11/09031-0, 15/17260-0, 14/23767-8)

ROCHA, BRENO PADOVEZI; RODRIGUES, ROGER AUGUSTO; GIACHETI, HERALDO LUIZ. The Flat Dilatometer Test in an Unsaturated Tropical Soil Site. GEOTECHNICAL AND GEOLOGICAL ENGINEERING, JUN 2021. (15/17260-0)

ROCHA, BRENO PADOVEZI; DE CARVALHO RODRIGUES, ANDRE LUIS; RODRIGUES, ROGER AUGUSTO; GIACHETI, HERALDO LUIZ. Using a Seismic Dilatometer to Identify Collapsible Soils. INTERNATIONAL JOURNAL OF CIVIL ENGINEERING, DEC 2021. (15/17260-0)

DOS SANTOS, ROBERTO A.; ROCHA, BRENO P.; GIACHETI, HERALDO L.. DMT for Load-Settlement Curve Prediction in a Tropical Sandy Soil Compared to Plate Load Tests. GEOTECHNICAL TESTING JOURNAL, v. 43, n. 1, p. 113-131, JAN 2020. (11/09031-0, 15/17260-0, 14/23767-8)

BRENO PADOVEZI ROCHA; BRUNO CANOZA DA SILVA; HERALDO LUIZ GIACHETI. Maximum shear modulus estimative from SPT for some Brazilian tropical soils. Soils and Rocks, v. 46, n. 1, 2023-03-10. (15/17260-0)