Capturing inelastic coupling of internal forces and exact vibration frequencies for 3 d Timoshenko beam finite elements

2016-08-28
Soydaş, Ozan
Sarıtaş, Afşin
A three dimensional (3d) nonlinear frame finite element based on Timoshenko beam theory is presented in this analytical study by utilizing Hu-Washizu principle with displacement, strain and stress independent fields in the variational form. The finite element approximation for the beam uses shape functions for section forces that satisfy equilibrium and discontinuous section deformations along the beam. The element is free from shear-locking, and the superiority of the proposed model is displayed under nonlinear material behavior and modal analysis. Results for the inelastic coupling of 3d internal forces with proposed model are compared with results obtained from other element models and exact solutions. Vibration analyses are carried out by the use of force-based consistent mass matrix, and verification is undertaken with closed form solutions and 3d solid finite element analyses results.
The 2016 World Congress on Advances in Civil, Environmental, and Materials Research (ACEM16)/The 2016 Structures Congress (Structures16), (28 August - 01 September 2016).

Suggestions

Modeling of the nonlinear behavior of steel framed structures with semi rigid connections
Sarıtaş, Afşin; Özel, Halil Fırat (null; 2015-07-21)
A mixed formulation frame finite element with internal semi-rigid connections is presented for the nonlinear analysis of steel structures. Proposed element provides accurate responses for spread of inelasticity along element length by monitoring the nonlinear responses of several crosssections, where spread of inelasticity over each section is captured with fiber discretization. Each material point on the section considers inelastic coupling between normal stress and shear stress. The formulation of the ele...
A Three dimensional mixed formulation nonlinear frame finite element based on hu-washizu functional
Soydaş, Ozan; Sarıtaş, Afşin; Department of Civil Engineering (2013)
A three dimensional nonlinear frame finite element is presented in this analytical study by utilizing Hu-Washizu principle with three fields of displacement, strain and stress in the variational form. Timoshenko beam theory is extended to three dimensions in order to derive strains from the displacement field. The finite element approximation for the beam uses shape functions for section forces that satisfy equilibrium and discontinous section deformations along the beam. Nonlinear analyses are performed by...
Numerical Modeling of Electromagnetic Scattering from Periodic Structures by Transformation Electromagnetics
ÖZGÜN, ÖZLEM; Kuzuoğlu, Mustafa (2016-09-22)
The transformation electromagnetics is applied to the modeling of electromagnetic scattering from periodic structures in conjunction with the finite element method with periodic boundary conditions. In a unit cell of periodic structure, a uniform mesh is used over a flat surface and the arbitrary periodic surface is modeled by a coordinate transformation. The major advantage of this approach is that arbitrary geometries can be handled by using a single and simple mesh. Therefore, repeated computations (such...
Efficient finite difference calculation of partial derivative seismic wavefield using reciprocity and convolution
Sheen, Dong-hoon; Tuncay, Kağan; Baag, Chang-eob; Ortoleva, Peter J. (null; 2004-01-01)
Seismic waveform inversion is commonly studied by the least-squares method which transforms the inverse problem to an iterative minization problem of residuals between the synthetic model response and observed data. One can solve this problem using the gradient method, the Gauss-Newton method or the full Newton method. The performance of the inverse method depends on the algorithm for calculating the partial derivative seismic wavefield due to perturbations in the subsurface. In this work, 2-D elastic stagg...
Efficient finite difference calculation of partial derivative seismic wavefield using reciprocity and convolution
Sheen, Dong-Hoon; Tuncay, Kağan; Baag, Chang-Eob; Ortoleva, Peter J. (2004-01-01)
Seismic waveform inversion is commonly studied by the least‐squares method which transforms the inverse problem to an iterative minization problem of residuals between the synthetic model response and observed data. One can solve this problem using the gradient method, the Gauss‐Newton method or the full Newton method. The performance of the inverse method depends on the algorithm for calculating the partial derivative seismic wavefield due to perturbations in the subsurface. In this work, 2‐D elastic stagg...
Citation Formats
O. Soydaş and A. Sarıtaş, “Capturing inelastic coupling of internal forces and exact vibration frequencies for 3 d Timoshenko beam finite elements,” presented at the The 2016 World Congress on Advances in Civil, Environmental, and Materials Research (ACEM16)/The 2016 Structures Congress (Structures16), (28 August - 01 September 2016)., Jeju, Korea, 2016, Accessed: 00, 2021. [Online]. Available: https://hdl.handle.net/11511/88105.