Marcelo Greco

Federal University of Minas Gerais | UFMG · Departamento de Engenharia de Estruturas (DEES)

The present work aims to compare results in aircraft joints, focusing on spar and skin regions, considering two levels of detail to understand the differences in the structural response using different types of modeling (numerical and semi-amalytical Rutman approach). Several studies were already performed to obtain the correct understanding of how...

LaDDAMecS passou a funcionar no início de 2015, sob coordenação do professor Dr. Marcelo Greco. Montado com apoio e recursos próprios do Departamento de Engenharia de Estruturas, hoje o laboratório atende às disciplinas das áreas de mecânicas dos sólidos, principalmente nos cursos de Engenharia Civil, Engenharia Aeroespacial e Engenharia Mecânica....

Current urban environments are home to multi-modal transit systems, extensive energy grids, a building stock, and integrated services. Sprawling neighborhoods are composed of buildings that accommodate living and working quarters. However, it is expected that the cities and communities of the future will face complex and enormous challenges, includ...

Autores: MARCELO GRECO, GABRIELA ARAUJO MACHADO, JULIANO DOS SANTOS BECHO Resumo: O presente trabalho trata do desenvolvimento e da divulgação de uma ferramenta computacional desenvolvida em linguagem de programação Python, destinada ao ensino da análise não linear de estruturas reticuladas, particularmente aplicada ao estudo de estruturas treliçad...

RESUMO: A obtenção de cargas críticas e modos de flambagem pelo método do elementos finitos exige que uma discretização adequada dos membros seja empregada, uma vez que trata-se de uma técnica de solução aproximada. Assim, a convergência da solução do problema de autovalor não linear depende exclusivamente do nível de refinamento da malha de elemen...

RESUMO: Análises estáticas geometricamente não lineares de estruturas reticuladas, realizadas através do método dos elementos finitos exigem que uma discretização adequada dos membros seja empregada, uma vez que trata-se de uma estratégia de solução aproximada. Assim, a convergência das respostas não lineares está condicionada exclusivamente ao nív...

Introduction Adolescent Idiopathic Scoliosis is a spinal deformity. Its development can be linked to hypokyphosis in the thoracic region. Objective The present study proposed to investigate, through the finite element method, the biomechanics of the immature thoracic spine segment T5-T10 in normal and rectified kyphosis under axial load, flexion a...

Besides structural engineering, rubber-like materials have been used in several fields such as bioengineering and medicine. Usually, these materials undergo, not only large displacements, but large deformations as well, and this requires a special attention to write a formulation both mathematically and physically consistent. To this end, one must...

A novel expression of the derivative of the right stretch tensor with respect to the deformation gradient is obtained by an alternative approach, which does not use the spectral/single-value decomposition of tensors involved.

Resumo: A modelagem em elementos finitos da fuselagem de um helicóptero AS350-B2 Esquilo é aplicada para simular a aplicação do amortecedor sintonizado por massa na cabine da aeronave. O objetivo é avaliar como os parâmetros que definem o sistema passivo de controle influenciam na redução da amplitude de vibração vertical. A análise modal é emprega...

The main purpose of this article is to discuss the use of the Lyapunov exponents to evaluate the integrity of structures. The use of such coefficients is examined in an analysis that considers the geometric and physical nonlinearities, aiming to ensure the applicability of the method in robust simulations. The material nonlinearity is modeled using...

Memorial referente ao processo de promoção para a Classe E (Professor Titular) na Universidade Federal de Minas Gerais

Python Positional Truss 3D for Windows (executable file). Type the name of input file (example: star.txt). Input file names are in capital letters in the folder. Have a little patience for the program to start as there are several Python libraries that are loaded.

Special Issue Information Dear Colleagues, The structural health monitoring of buildings constitutes an area of research dedicated to ensuring the safety, durability and efficiency of constructed environment. Computational and experimental techniques are used to assess the integrity of buildings along time and to detect potential damage based on...

Citation: Lanes, R.M.; Greco, M.; Almeida, V.d.S. Viscoelastic Soil-Structure Interaction Procedure for Building on Footing Foundations Considering Consolidation Settlements. Buildings 2023, 13, 813. Abstract: This paper presents a numerical methodology to analyze frame structures supported on footing foundations subjected to slow strains caused by...

RESUMO Colapsos, rupturas e danos estruturais de pontes rodoviárias são constantemente associados às falhas na gestão de manutenção dessas obras e têm sido divulgados com maior frequência, pressionando a engenharia em todo o mundo para oferecer respostas que resultem em um controle adequado do comportamento dessas estruturas. Nesse contexto, a ciên...

The purpose of this article is to contribute to the discussion on the repercussions of the use of different strain measures in structural analyzes carried out using numerical methods, especially regarding computational cost. In the present study the Positional Finite Element Method applied to truss structures is used. The Green, Biot, Logarithmic,...

Resumo. Um estudo comparativo para a simulação de modelos voltados para a Interação Solo-Estrutura é apresentado. As deformações da superestrutura são computadas pelo Método dos Elementos Finitos, enquanto os deslocamentos do solo são definidos a partir de métodos analíticos e também numéricos. Analiticamente, os deslocamentos do solo se fundamenta...

Resumo. Neste trabalho é apresentado um estudo comparativo da utilização de três diferentes modelos reológicos adotados frequentemente para descrição do comportamento viscoelástico de fluência em materiais sólidos. Os modelos reológicos utilizados neste estudo são os modelos de Boltzmann, de Zener e de Kelvin-Voigt. Por fim, é apresentado um quadro...

The definition of objectivity plays an important role in the enunciation of the Invariance of Material Response (IMR) in the development of the Continuum Mechanics. Unfortunately, the most used framework to formulate the IMR-based on monitoring of one motion by two observers-shows somewhat inconsistency with the objectivity definition. Besides, mos...

The main purpose of this article is to present an objective, symmetrical and versatile family of strain measures based on the hyperbolic tangent function, both in its uniaxial and in its tensor form (3D): the Generalized Hyperbolic Tangent (GHT) strain measure. It is a goal of this work to examine the properties of the strain measure created and to...

The present paper aims to test recent (Truly self-starting two sub-step method and three-parameter single-step implicit method) and classical (Generalized-α, HHT-α, and WBZ-α methods) time integration methods using the geometrically nonlinear Positional Finite Element Method (PFEM). The numerical formulation is based on the total Lagrangian approac...

During last years, the number of Unmanned Aircraft Systems (UAS), popularly known as drones, operating in the sky of urban centers has quite increased. Associated with this growth, the risk of airborne impacts between such vehicles and manned aircrafts, caused intentionally or not, has also increased. Aiming to understand the phenomena that occur d...

Purpose In this paper the use of classical strain measures in analysis of trusses at finite deformations will be discussed. The results will be compared to the ones acquired using a novel strain measure based on the Hyperbolic Sine function. Through the evaluation of results, algebraic development and graph analysis, the properties of the Hyperboli...

The advancement of engineering structures is increasingly leading to slender and light elements that require more complex analysis. Instability problems are frequently observed in such situations, and their study is of fundamental importance. Numerical methods are commonly used in those analyses. It is proposed in this work to use a variation of th...

Computational finite element analysis has been used in investigations of the spine, contributing to the understanding of its biomechanical behavior. Intervertebral discs (IVD) are structures that make the connection between the vertebrae, allowing movement between it and, consequently, increasing the mobility of the spine and been one of the most c...

Resumo. Neste trabalho pretende-se contribuir com o estudo de medidas de deformação e seus pares conjugados de tensão aplicados à formulação posicional do Método dos Elementos Finitos (MEFP). São apresentadas seis medidas de deformação para a referida formulação. As medidas de deformação podem ser usadas em problemas geometricamente não-lineares. A...

Resumo. Resumo Keywords: MEC3D, MatLab, Integração numérica, Elementos de contorno 1. INTRODUÇÃO O Método dos Elementos de Contorno (MEC) tende a oferecer mais vantagens do que o Método dos Elementos Finitos (MEF) para problemas associados a meios infinitos ou semi infintos, dado que, possui formulações pormenorizadas para cada aplicação, baseando-...

A numerical procedure is presented to avoid the divergence problem during the iterative process in viscoelastic analyses. This problem is observed when the positional formulation of the finite element method is adopted in association with the finite difference method. To do this, the nonlinear positional formulation is presented considering plane f...

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Unconventional materials, such as elastomers, polymers, composites, and intelligent materials, have been widely used in mechanical components and structural elements in a diverse range of engineering areas such as infrastructure, civil construction, mechanical and aerospace industries, among others. In this sense, the study and characterization of...

Elastomeric bearing pads are responsible for transfering loads at the junction between beams and columns of bridges and viaducts, providing restrict freedom of movement in the superstructure. The elastomeric material of bearing pads is a synthetic rubber reinforced with carbon black particles and subjected to a process of vulcanization, also repres...

Elastomeric bearing pads are responsible for transferring loads at the junction between beams and columns of bridges and viaducts, providing restrict freedom of movement in the superstructure. The elastomeric material of the bearing pad is a synthetic rubber reinforced with carbon black particles and subjected to a process of vulcanization, also re...

The procedure of structural design for aircraft parts is widely known and discussed in the academy and in the industry, although it has been improved along the time. It is based on a detailed process of aerodynamics loads study coupled or not with specifications required by regulatory agencies. Further, several interactions of analysis are done to...

O controle do estado de condição de cada elemento da infraestrutura de transportes é fundamental para assegurar a operação do sistema a partir de um nível de segurança definido. Para a gestão desses elementos é necessário conhecer as características do parque de obras nacional, seu histórico, estado atual e a previsão do seu estado futuro através d...

Rubber-like materials are well known for their mechanical properties and are currently used in many applications ranging from shoes and school supplies to tires, vibration dampers and springs. They are very flexible materials due to their structure and high molecular weight, besides having a good resilience, high elasticity, great deformation capac...

Over the years, new materials have been developed and their applications involve different studies regarding their use and behavior. In this context, it is possible to note the growing use of devices made with rubber and steel, called support devices, which are responsible for transferring stresses from bridge beams to the supporting columns. The u...

In aeronautics, the risk of an airborne impact between an aircraft and other elements such as birds, hails and other small vehicles must be evaluated. The impact of an Unmanned Aerial Systems (UAS), for example, can be more critical for an aircraft than a bird strike, as reported in a study published by the Federal Aviation Administration (FAA) in...

Beautiful Ballet of a Three Bars Mechanism with simple joints - by Daniel Boy Vasconcellos

Beautiful Ballet of a Three Bars Mechanism with viscoelastic Kelvin-Voigt joints - by Daniel Boy Vasconcellos

This article aims to explore the application of an evolutionary optimization technique for multi-objective optimization problems using as criteria the minimization of von Mises maximum stress and minimization of the maximum growth of internal structural strain energy. To evaluate the overall effect on the optimal design configuration, due to the re...

Resistência dos Materiais: Um guia prático aborda os conteúdos clássicos da resistência dos materiais. Organizado em cinco capítulos, apresenta, segundo a experiência dos autores, os tópicos mais importantes ensinados nas escolas de Engenharia do Brasil, abordando os seguintes temas: equilíbrio, solicitação axial, corte, torção em seções circulares...

Elastomeric components are widely used in the engineering field since their mechanical properties can vary according to a specific condition, enabling their applications under large deformations and multiaxial loading. In this context, the present study seeks to investigate the main challenges involved in the finite element hyperelasticity simulati...

Resumo Escoliose idiopática do adolescente (EIA) atinge de 2% a 4% de jovens no Brasil. Repetidas exposições aos exames radiológicos, no acompanhamento desta deformidade, podem ser danosos à saúde. O objetivo deste estudo é apresentar um protocolo de fotogrametria, como método não ionizante para quantificação da escoliose, e relacioná-lo ao método...

Bridge Management aims to provide an appropriate support to decision-making for maintenance, rehabilitation and repair strategies under constraint of limited budgets. In this regard, the Federal Brazilian Department of Transportation (DNIT) has developed the SGO - a Brazilian Bridge Management System (B-BMS) - and promoted the most comprehensive ro...

The search for representative resistant systems for a concrete structure requires deep knowledge about its mechanical behavior. Strut-and-tie models are classic analysis procedures to the design of reinforced concrete regions where there are stress concentrations, the so-called discontinuous regions of the structure. However, this model is strongly...

The CubeSat initiative began as an educational tool for Aerospace Engineering students and, although this kind of technology has proven itself to be a reliable way of achieving complex missions, it still has an important role as a manner of training and educating human resources. In this sense, and with the objective of developing Aerospace Enginee...

Resumo: Diante da necessidade da construção de estruturas cada vez mais eficientes e econômicas, estudos referentes a problemas de instabilidade são temas de grande relevância. A eficiência das estruturas está também relacionada com o menor consumo de material para a construção da mesma. Com isso, há a necessidade de construção de elementos estrutu...

Resumo: Os elastômeros são, atualmente, muito utilizados em diversos setores industriais devido a sua elevada capacidade de deformação e amortecimento, alta flexibilidade e resiliência, além de uma ótima recuperação elástica. Suas relações constitutivas são altamente não-lineares e caracterizadas por funções de energia de deformação que devem ser d...

Background: The gold standard method of monitoring the evolution of scoliosis has been serial standing, posteroanterior, full-length spine radiographs with curvature measurements using the Cobb method. However, over the course of follow-up, patients can receive high radiation doses. Various studies have shown that repeated exposure to radiation in...

Structural engineering demands increasingly lighter systems, which can cause instability problems and compromise performance. A high slenderness index of a structural element makes it susceptible to instability. It is important to understand the problem, the limits of stability, and its postcritical behavior. An example that can occur in collapsed...

A previsão das condições futuras dos componentes de infraestrutura tornou-se o principal diferencial na gestão moderna de pontes em todo o mundo. O conhecimento da provável condição da ponte ou da sua segurança a qualquer tempo é basilar para a obtenção do melhor gerenciamento estratégias, através da priorização das intervenções de manutenção, refo...

A otimização topológica (OT) de estruturas em estado plano em regime estático linear é realizada neste trabalho aplicando aformulação baseada no método heurístico clássico evolucionário ESO e sua variante SESO associado ao método dos elementos finitos. Avaliam-se assim exemplos clássicos da literatura que apresentam resultados da OT, que busca a mi...

This paper presents the development of a formulation, based on Positional Finite Element Method, to describe the viscoelastic mechanical behavior of space trusses. The numerical method used was chosen due to its efficiency in the applications concerning nonlinear numerical analyses. The formulation describes the positional variation over time under...

Deformity in adolescent thoracic spine has high prevalence worldwide. The objective of this work was to study the biomechanical behavior on the thoracic spines of adolescents under asymmetric ligament load in kyphosis and rectified kyphosis. Two finite element models of an adolescent thoracic segment, T5–T10, were generated with every bone componen...

Structural optimization has received increasing attention in several different areas of engineering and has been identified as the most challenging and economically rewarding task in the field of structural design. In this context, the current paper proposes a methodology based on Evolutionary Structural Optimization (ESO) that corresponds to an ev...

The thermal effects of problems involving deformable structures are essential to describe the behavior of materials in feasible terms. Verifying the transformation of mechanical energy into heat it is possible to predict the modifications of mechanical properties of materials due to its temperature changes. The current paper presents the numerical...

Almost all road vehicles have wheels with pneumatic tires. Tire development made possible to the automotive industry to design comfortable and safe road vehicles. According to the Federal Motor Vehicle Safety Standards (FMVSS) some test procedures for tire endurance, high-speed performance and strength are required. Tire strength, for example, is v...

Resumo O Departamento Nacional de Infraestrutura de Transportes (DNIT) modernizou o Sistema de Gerenciamento de Obras de Arte Especiais (SGO), desenvolvendo sua nova versão entre os anos de 2008 e 2013. Paralelamente ao desenvolvimento do software, o DNIT realizou o mais abrangente inventário das pontes rodoviárias sob sua administração, promovendo...

This paper analyzes the dynamic response of space and plane trusses with geometrical and material nonlinear behaviors using different time integration algorithms, considering an alternative Finite Element Method (FEM) formulation called positional FEM. Each algorithm is distinguished from each other by its specific form of position, velocity, accel...