Papers by Maria do Carmo Reis Cavalcanti
Aos que me acompanharam e Incentivaram nessa Jornada, e de cuJas vidas subtraí, em parte, minha p... more Aos que me acompanharam e Incentivaram nessa Jornada, e de cuJas vidas subtraí, em parte, minha presença e minha atenção.
Infrastructures, Mar 22, 2023
This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY
Infrastructures, 2023
This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY
Infrastructures, 2023
This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY
Congresso Brasileiro de Mecânica dos Solos e Engenharia Geotécnica
Infrastructures
Shallow tunnels induce surface displacements which can cause damage to existing structures; an ad... more Shallow tunnels induce surface displacements which can cause damage to existing structures; an adequate evaluation of their settlement trough is of paramount importance. Nowadays, it becomes even more critical when dealing with an underground occupation where the green stress field has already been disturbed by previous excavations. Since the end of the last century, many researchers have explored the subject. Some empirical methodologies have been developed based on data from actual cases, sometimes associated with numerical analysis. The present work used plane strain numerical analysis of different geometric arrangements of side-by-side twin tunnels for different depths and distances between tunnel axes to evaluate its compatibility with some of the proposed methods to adjust the settlement profile of the second cavity. It was observed that the discussed methodologies have similar results for maximum settlement and its eccentricity. Nevertheless, the behavior of the trough width ...
Infrastructures
Tailings dam accidents emphasize the importance of an adequate understanding of the strength para... more Tailings dam accidents emphasize the importance of an adequate understanding of the strength parameters of tailings to improve the efficiency and effectiveness of the design, construction, and operation of such structures. Usually, the tailings strength is addressed in a deterministic manner. However, a statistical approach would better represent their behavior due to its inherent heterogeneity. The literature about tailings strength distribution is relatively rare or superficial, which impairs the probabilistic analyses which are essential for risk management. Therefore, this article focuses on the probability density function (PDF) of the effective friction angle (ϕ′) of iron ore tailings from the reservoir of Germano dam, Mariana, Brazil, based on data from publicly available CPTu tests. The influence of the relative density (Dr), and the presence of plastic layers amidst the sand tailings on the strength of the sand are also discussed herein. Several correlations were employed t...
Congresso Brasileiro de Mecânica dos Solos e Engenharia Geotécnica
Uma análise dinâmica de estabilidade de taludes pelo método de elementos finitos permite represen... more Uma análise dinâmica de estabilidade de taludes pelo método de elementos finitos permite representar melhor os esforços gerados como resultado da aplicação de um sismo, além de incluir na análise outros fatores, como excesso de pressão dos poros, resistências pós-sísmicas e possíveis zonas de liquefação. Desse modo, são levados em consideração os elementos deixados de lado pelos métodos de equilíbrio limite, que podem afetar a estabilidade da estrutura analisada. O estudo do efeito dos sismos na estabilidade de taludes merece uma atenção especial, em função da complexidade envolvida. Muitas vezes, este efeito é determinante na segurança de uma região ou obra, que pode vir a ser afetada pela ruptura de um talude. Dito isso o objetivo desse estudo tem como foco apresentar soluções para um melhor entendimento dos parâmetros utilizados numa analise dinâmica de um talude, utilizando um tratamento de dados coerentes com a complexidade determinada. Para isso, utilizou-se o software de elementos finitos, GeoStudio 2019, em específico as plataformas SLOPE/W, para modelagem estática, e QUAKE/W, para uma análise de estabilidade dinâmica do maciço.
Geotech Geol Eng, 2022
The Manso Dam, in the Brazilian State of Mato Grosso, intended for flood control and electricity ... more The Manso Dam, in the Brazilian State of Mato Grosso, intended for flood control and electricity generation, was built by a state-owned energy company in partnership with the private sector. In order to reduce costs and minimize the environmental impact of the project, the private consortium proposed changes to the preliminary design, which were reassessed with the participation of the Federal University of Rio de Janeiro. The design and the behavior of the dam are discussed in this paper. The main section of the Manso Dam, 73 m high, has rockfill shells and a core of compacted soil. For the core, colluvial and residual soils derived from the necessary excavations for the concrete structures and dam foundation were chosen in order to reduce both Keywords Dam cores Á Random fill Á Seepage analysis Á Deformation analysis Abbreviations c Cohesion u Angle of shearing resistance
Geotechnical and Geological Engineering, Nov 10, 2021
The Manso Dam, in the Brazilian State of Mato Grosso, intended for flood control and electricity ... more The Manso Dam, in the Brazilian State of Mato Grosso, intended for flood control and electricity generation, was built by a state-owned energy company in partnership with the private sector. In order to reduce costs and minimize the environmental impact of the project, the private consortium proposed changes to the preliminary design, which were reassessed with the participation of the Federal University of Rio de Janeiro. The design and the behavior of the dam are discussed in this paper. The main section of the Manso Dam, 73 m high, has rockfill shells and a core of compacted soil. For the core, colluvial and residual soils derived from the necessary excavations for the concrete structures and dam foundation were chosen in order to reduce both the cost and environmental damage that would result from borrow/disposal. Such composite clay, gravel and cobbles of different sizes and degrees of weathering is generally referred to in the literature as random fill, and because is not typically used in dam cores, laboratory and field tests were then performed. Parameter evaluation and Finite Element (FEM) analyses of seepage and deformation were carried out. The seepage analysis was carried out for the maximum normal reservoir level, and the results were confirmed by the field monitoring data, enabling the establishment of safety levels (alert and emergency conditions). Embankment construction and first reservoir filling were simulated with the FEM, yielding, as expected, stress concentrations in the more rigid materials, such as the filters and transitions. During reservoir filling, seepage forces induced horizontal displacements in the downstream direction and reduction in effective stresses in the upstream region due to submersion. The predicted settlement distribution was compatible with field monitoring data. Construction was completed in 2010 and the dam has been operating normally ever since.
COPPE - UFRJ - Master Thesis, 1990
Este trabalho descreve estudo sobre a distribuicao de tensoes em torno de estruturas de concreto ... more Este trabalho descreve estudo sobre a distribuicao de tensoes em torno de estruturas de concreto que atravessam barragens de terra. Os estudos consistiram de analise pseudo-tridimensional, que tira proveito dos estados planos de deformacao, transversal pelo eixo da galeria e longitudinal pelo eixo da estrutura de barramento, utilizando um programa bidimensional de elementos finitos. Foram analisadas duas estruturas nas quais haviam sido instaladas celulas de pressao total na interface solo/estrutura, e os resultados obtidos nas analises pseudo-tridimensionais foram aferidos pela comparacao com os valores de tensao registrados pela instrumentacao. Complementando os estudos, foi avaliada a influencia da geometria do terreno natural, deformabilidade da estrutura e relacao entre os modulos de deformabilidade da fundacao e do aterro, na distribuicao longitudinal de tensoes normais a estrutura; tendo sido tambem analisada a perturbacao provocada no campo de tensoes pela presenca da intrus...
El presente trabajo pretende demostrar las ventajas de considerar el regimen de flujo transitorio... more El presente trabajo pretende demostrar las ventajas de considerar el regimen de flujo transitorio en el analisis de estabilidad de talud aguas arriba para la situacion de reduccion rapida de una presa de tierra homogenea. Se llevaron a cabo analisis de estabilidad de taludes aguas arriba, considerando la presion de poro / succion para analisis de flujo transitorio que simula la reduccion rapida del embalse. Los analisis comprendieron diferentes geometrias del talud aguas arriba (de 1V: 1.1H a 1V: 2.5H), alturas que varian de 10 m a 50 m, asi como varios materiales de baja permeabilidad (SM, SM-SC, SC, ML, ML-CL, CL, MH y CH). Ademas, las ecuaciones que relacionan el factor de seguridad con dichos taludes o la altura de la presa se ajustaron a los datos de analisis, para definir el talud minimo para una determinada altura de la presa o la altura maxima para un determinado talud aguas arriba. Los resultados han demostrado que: teniendo en cuenta la condicion de flujo transitorio, incl...
Geotechnical and Geological Engineering
Thesis Chapters by Maria do Carmo Reis Cavalcanti
COPPE - UFRJ - DSc Thesis, 2002
The present work discusses the application of boundary elements, with time independent fundament... more The present work discusses the application of boundary elements, with time independent fundamental solutions, to solve Biot’s consolidation equations for poroelastic saturated media. The time marching scheme divides the analysis in small steps and applies finite differences to integrate the diffusion equations as well as to determine the time derivative of the total volumetric stresses. Each phase of the consolidation phenomenon is solved independently within each time step, and the exchange of common data associated to an iterative procedure provides means of coupling the two analyses. A starting elastostatic analysis under constant volume is carried out to evaluate the initial values of total stresses and pore-pressure. The media heterogeneity is simulated by means of corrective stress and velocity field, respectively for the elastostatic and diffusion phases.
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Papers by Maria do Carmo Reis Cavalcanti
Thesis Chapters by Maria do Carmo Reis Cavalcanti