Banca de DEFESA: DANIELA TORO ROJAS

Uma banca de DEFESA de DOUTORADO foi cadastrada pelo programa.
STUDENT : DANIELA TORO ROJAS
DATE: 23/08/2024
TIME: 14:00
LOCAL: Videoconferência
TITLE:

"STUDY OF KARST SYSTEMS USING THE MATERIAL POINT METHOD"

KEY WORDS:

Karst system, Material Point Method, Tailing Dams, Damage Model.

PAGES: 305
BIG AREA: Engenharias
AREA: Engenharia Civil
SUBÁREA: Geotécnica
SUMMARY:

Karst regions have been studied from a geological perspective for over a century. It is estimated that karst coverage represents around 20% of the Earth's surface. In Brazil, 19 karst regions have been identified across its territory. In this context, this thesis investigates the geomechanical behavior of karst systems and the problems arising from their development and collapse using the Material Point Method (MPM). The research reviews the geology and geomechanics of these systems and the most commonly used numerical methods for evaluating problems in geotechnical engineering. It delves into concepts related to MPM, elastoplasticity, constitutive models, and damage models, which subsequently support a parametric analysis evaluating collapse and subsidence mechanisms in karst environments using the selected numerical method implemented in Anura 3D software. Within the context of the Iron Quadrangle, one of Brazil's karst regions, a case study on the impacts of karst collapse and subsidence on tailings dams is conducted. The region's complex geology facilitates the formation of karst features that threaten the stability of the dams. The case studies show that the presence of caves and geological discontinuities can lead to severe instabilities, directly influencing the failure mechanisms and post-failure kinematics of the dams. Finally, the thesis validates the HyperDamage model in GeoStudio software, demonstrating its capability to represent the behavior of rocks and quasi-brittle materials. This model, based on hyperbolic behavior and continuous damage mechanics, proved robust after validations with laboratory tests. Future implementations in other software, such as Anura 3D, could expand applications in rock mechanics and karst feature evaluation.

COMMITTEE MEMBERS:
Externo à Instituição - JONATHAN DA CUNHA TEIXEIRA - UFAL
Externo à Instituição - IGOR FERNANDES GOMES - UFPE
Interno - 2161425 - JUAN FELIX RODRIGUEZ REBOLLEDO
Presidente - 1549489 - MANOEL PORFIRIO CORDAO NETO
Interno - 404227 - MARCIO MUNIZ DE FARIAS