Blocos de concreto armado sobre seis estacas: simulação numérica e dimensionamento pelo método de bielas e tirantes

Oliveira, Diego Sales de; Barros, Rodrigo; Giongo, José Samuel

doi:10.1590/s1983-41952014000100002

Cited by 3 publications

(1 citation statement)

References 2 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…O número de estacas no bloco depende dos esforços solicitantes na base do pilar, da capacidade geotécnica do solo e das condições disponíveis de construção, possibilitando a definição do tipo de estaca e a determinação de sua capacidade portante (OLIVEIRA et al, 2014).…”

Section: Introductionunclassified

Análise não linear estática de bloco sobre estaca baseada na Mecânica do Dano Contínuo

Souza

2015

Semina: Tech. Ex.

View full text Add to dashboard Cite

O bloco sobre estacas é um importante elemento estrutural cuja função é transferir as ações da superestrutura para um grupo de estacas. A inspeção visual do comportamento do mesmo sob condições de serviço geralmente não é possível e, além disso, o conhecimento do seu verdadeiro desempenho estrutural é uma necessidade vital para a estabilidade global das construções. Neste artigo, uma análise não linear bidimensional é realizada, por meio do Método dos Elementos Finitos, de um bloco rígido de concreto armado sobre duas estacas encontrado na literatura. Adota-se para o material concreto um modelo constitutivo baseado na Mecânica do Dano Contínuo, com a possibilidade de prever um comportamento diferenciado à tração e à compressão. O aço é descrito por um modelo elastoplástico bilinear. A trajetória de equilíbrio é obtida com a técnica de iteração Comprimento de Arco em associação com o Método de Newton -Raphson. Os resultados numéricos obtidos com o código computacional desenvolvido são confrontados com os resultados experimentais e numéricos disponíveis e com a solução analítica, e têm o objetivo de avaliar a potencialidade da modelagem proposta como uma ferramenta numérica de investigação quanto à determinação da força de ruptura e a distribuição do dano no bloco. ResumoThe piles cap is an important structural element whose function is to transfer the actions of the superstructure for a group of piles. The visual inspection of the piles cap behavior under service conditions is not possible and, in addition, the knowledge of its actual structural performance is a vital necessity for the constructions overall stability. In this paper, a two-dimensional nonlinear analysis is carried out, by means of Finite Element Method, of a reinforced concrete pile caps with two piles found in the literature. It adopts for the material concrete a constitutive model based on the Continuum Damage Mechanics, with the possibility to provide a tensile and compression differentiated behavior. The steel is described by an elastoplastic bilinear model. The equilibrium path is achieved by Arc Length iteration technique in association with the Newton -Raphson Method. The numerical results obtained with the developed computational code are compared with the available experimental and numerical results and the analytical solution, and have the objective of evaluate the potential of the proposed modeling as an investigation numerical tool to determine the rupture force and the damage distribution in the piles cap.

show abstract

Section: Introductionunclassified

Análise não linear estática de bloco sobre estaca baseada na Mecânica do Dano Contínuo

Souza

2015

Semina: Tech. Ex.

View full text Add to dashboard Cite

show abstract

Design of Rigid Pile Caps through an Iterative Strut-and-Tie Model

Araújo

2016

ACT

View full text Add to dashboard Cite

The aim of this work is to present a strut-and-tie model for design of reinforced concrete pile caps. The model considers both failure by crushing of the compressed struts and by yielding of the tie reinforcement. Unlike some traditional models, crushing of the compressed concrete is not checked at the section in direct contact with the column base (column/pile cap interface). In this work, crushing of concrete is verified in a section at a certain depth inside the pile cap. Thus, this verification is replaced by determining the height of the nodal zone at the top of the pile cap required not to cause crushing of the struts. An iterative algorithm is used for this purpose. Comparison with a large number of experimental results available in the literature demonstrates the effectiveness of the proposed model for the design of concrete pile caps. Numerical examples of practical use of the model are also presented.

show abstract

Numerical Modeling of Four-Pile Caps Using the Concrete Damaged Plasticity Model

Spozito,

Rodrigues,

Santos

et al. 2024

Buildings

View full text Add to dashboard Cite

Four-pile caps made from concrete are essential elements for the force transfer from the superstructure to piles or pipes. Due to the difficulties in carrying out full-scale tests and all the instrumentation involved, the use of numerical models as a way to study the mechanical behavior of these elements presents itself as a good alternative. Such numerical studies usually provide useful information for the update and improvement of normative standards and codes. The concrete damaged plasticity (CDP) constitutive model, which combines damage and plasticity with smeared-crack propagation, stands out in the simulation of reinforced concrete. This model is composed of five parameters: dilatation angle (ψ), eccentricity (ϵ), ratio between biaxial and uniaxial compressive strength (σbo/σco), failure surface in the deviator plane normal to the hydrostatic axis (Kc), and viscosity (μ). For unidimensional elements, the values of the CDP parameters are well defined, but for volumetric elements, such as concrete pile caps, there is a gap in the literature regarding the definition of these values. This fact ends up limiting the use of the CDP on these structural elements due to the uncertainties involved. Therefore, the aim of this research was to calibrate two numerical models of concrete four-pile caps with different failure modes for the evaluation of the sensitivity of the CDP parameters, except for ϵ, which remained constant. As a result, the parameters σbo/σco and Kc did not significantly influence the calibration of the force × displacement curves of the simulated structures. Values of ψ and μ equal to 36° and 1 × 10−4, respectively, are recommended for “static” analysis, while for “quasi-static” analysis, ψ values ranging between 45° and 50° are suggested according to the failure mode. The results also showed to be sensitive to the constitutive relation of concrete tensile behavior in both modes of analysis. For geometric parameterization, the “static” analysis is recommended due to the lower coefficient of variation (3.29%) compared to the “quasi-static” analysis (19.18%). This conclusion is supported by the evaluation of the ultimate load of the numerical models from the geometrically parametric study compared to the results estimated by an analytical model.

show abstract

Blocos de concreto armado sobre seis estacas: simulação numérica e dimensionamento pelo método de bielas e tirantes

Cited by 3 publications

References 2 publications

Análise não linear estática de bloco sobre estaca baseada na Mecânica do Dano Contínuo

Análise não linear estática de bloco sobre estaca baseada na Mecânica do Dano Contínuo

Design of Rigid Pile Caps through an Iterative Strut-and-Tie Model

Numerical Modeling of Four-Pile Caps Using the Concrete Damaged Plasticity Model

Contact Info

Product

Resources

About