A multilayered 3D hexahedral finite element with rotational DOFs

Frattura Ed Integrità Strutturale

2020

In this work, the small-strain elastoplastic behavior of structures is analyzed using an improved nonlinear finite element formulation. In this framework, an eight-node quadrilateral finite element denoted PFR8 (Plane Fiber Rotation) that belongs to the set of elements with rotational degrees of freedom is developed. Its formulation stems from the plane adaptation of the Space Fiber Rotation (SFR) concept that considers virtual rotations of nodal fiber within the element. This approach results in an enhancement of the displacement vector approximation. Von-Mises yield criteria have been applied for yielding of the materials along with the associated flow rule. Newton-Raphson method has been used to solve the nonlinear equations. To assess the performance of the proposed element, benchmark problems are addressed and the results are compared with some analytical and numerical solutions from the literature.

Section: Kinematics Of the Pfr8 Finite Elementmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Elastoplastic analysis of plane structures using improved membrane finite element with rotational DOFs: Elastoplastic analysis of plane structures

Ayadi

Frattura Ed Integrità Strutturale

2020

“…The approximation of the part corresponding to the rotation of space fiber is quadratic in terms of  ,  and  . The element stiffness matrix is integrated exactly using a four-point numerical quadrature (Npi = 4) [15].…”

Section: The Sfr Concept Finite Element Approximationmentioning

confidence: 99%

A Four-Node Tetrahedral Finite Element Based on Space Fiber Rotation Concept

Acta Universitatis Sapientiae, Electrical and Mechanical Engineering

2019

Self Cite

The paper presents a four-node tetrahedral solid finite element SFR4 with rotational degrees of freedom (DOFs) based on the Space Fiber Rotation (SFR) concept for modeling three-dimensional solid structures. This SFR concept is based on the idea that a 3D virtual fiber, after a spatial rotation, introduces an enhancement of the strain field tensor approximation. Full numerical integration is used to evaluate the element stiffness matrix. To demonstrate the efficiency and accuracy of the developed four-node tetrahedron solid element and to compare its performance with the classical four-node tetrahedral element, extensive numerical studies are presented.

“…The response of these two elements in the linear static regime was examined through a series of benchmarks where the findings show a better accuracy than the classical first order hexahedral element and close to the quadratic 20-node hexahedral element. In the same vein, the SFR concept was adopted in the works of Meftah et al [27,28] to develop a six-node wedge element SFR6 and a multilayered hexahedral element SFR8M. In recent developments on the SFR elements, the SFR8 and the SFR8I elements were implemented into the commercial code ABAQUS by means of the UEL interface to address nonlinear geometric problems [29].…”

Section: Introductionmentioning

confidence: 99%

An Eight-Node Hexahedral Finite Element with Rotational DOFs for Elastoplastic Applications

Ayadi

Acta Universitatis Sapientiae, Electrical and Mechanical Engineering

et al. 2019

Self Cite

In this paper, the earlier formulation of the eight-node hexahedral SFR8 element is extended in order to analyze material nonlinearities. This element stems from the so-called Space Fiber Rotation (SFR) concept which considers virtual rotations of a nodal fiber within the element that enhances the displacement vector approximation. The resulting mathematical model of the proposed SFR8 element and the classical associative plasticity model are implemented into a Fortran calculation code to account for small strain elastoplastic problems. The performance of this element is assessed by means of a set of nonlinear benchmark problems in which the development of the plastic zone has been investigated. The accuracy of the obtained results is principally evaluated with some reference solutions.