Banca de DEFESA: Thiago Luiz Freire Rodrigues

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
STUDENT : Thiago Luiz Freire Rodrigues
DATE: 06/09/2023
TIME: 14:00
LOCAL: Plataforma Teams
TITLE:

NUMERICAL MODELING OF STEEL FIBER REINFORCED CONCRETE USING COHESIVE ELEMENTS

KEY WORDS:

Finite Elements, Cohesive Elements, Steel Fiber Reinforced Concrete, Concrete Cracking

PAGES: 112
BIG AREA: Engenharias
AREA: Engenharia Civil
SUBÁREA: Estruturas
SPECIALTY: Estruturas de Concreto
SUMMARY:

The quasi-brittle behavior of concrete can lead to the formation of cracks in structures built with this material. However, the addition of steel fibers has proven highly effective in enhancing the post-cracking behavior of concrete, increasing its energy absorption capacity and reducing the likelihood of structural damage. As a result, steel fiber-reinforced concrete (SFRC) can withstand higher loads, better resist weather conditions and chemical attacks, and have a longer service life compared to conventional concrete. In this context, this research introduces a numerical approach to simulate the behavior of SFRC. The simulation of concrete behavior (including fracture) is carried out using volumetric finite elements combined with cohesive elements. A linear elastic model is employed for the volumetric elements, while the cohesive elements are based on the theory of plasticity and fracture mechanics, enabling the prediction of crack initiation and propagation. Steel fibers are modeled using two-node finite elements (truss elements) with a one-dimensional perfect elastoplastic constitutive model. They are positioned using a uniform and isotropic random distribution, accounting for the effect of mold walls. Special contact elements are utilized to model the complex and nonlinear behavior of the interface between the fiber and the matrix, capable of predicting relative displacements between the concrete and steel fibers. The validation of the method is performed through numerical examples involving sets of fibers, with load-displacement curves aligning with literature experiments and fracture patterns corresponding to expected failure modes. The comparison with experimental results reaffirms that the application of this numerical strategy in modeling SFRC behavior is highly promising, serving as a significant tool to further comprehend the diverse aspects governing the failure process of this material.

COMMITTEE MEMBERS:
Presidente - 1825564 - RAUL DARIO DURAND FARFAN
Interno - 404840 - WILLIAM TAYLOR MATIAS SILVA
Externo ao Programa - 1619095 - MARCUS VINICIUS GIRAO DE MORAIS - UnBExterno à Instituição - JEAN MARIE DESIR - UFRGS