Validation of Alternative Beam T-Junction Fem Models for Complex Tubular Structures

Abstract

The finite element analysis of tubular structures is typically based on models constructed employing beam-type elements. This modeling technique provides a quick and computationally efficient option for calculation. Nevertheless, it shows a series of limitations related to the simplicity of this type of element, among which the inability of accounting for the stiffness behavior at the joint level is of notable importance when modeling complex tubular structures. Despite these limitations, the alternative of simulating complex tubular structures with shell- or volume-type elements is highly costly due to the complexity of the modeling process and the computational requirements. Previous research has proposed alternative beam models that improve the estimations when modeling these structures. These research validations were limited to simple models. This paper presents a validation process utilizing a previously developed beam T-junction model in a complex tubular structure, intended to be representative for buses’ and coaches’ upper structures. Results obtained reveal that the accuracy of beam element type models can be significantly improved with the adequate implementation of elastic elements to account for the real junction stiffness.

On the Application of Neural Networks Trained with FEM Data for the Identification of Stiffness Parameters of Improved Mechanical Beam Joints

“…Even for simple tubular structures, like the one presented in Figure 6, the model proposed by [3] would not be applicable, as none of the corner junctions could be characterized as either T1 or T2 junctions. In [9], the authors performed a validation of the alternative beam model of [3] on a complex tubular structure. Although an improvement in the accuracy was demonstrated with respect to ordinary beam-element-type models, limitations were encountered related to the fact that, when analyzing real structures, it is not always obvious to classify T-junctions as T1 or T2 (Figure 5), and that in many cases, more complex junctions simply do not fit in a six-elastic-element alternative beam model.…”

Special Issue: “Computational Mechanics of Structures and Materials”

“…Badea et al highlighted the limitations of usual finite element models in dealing with tubular structures. By means of a previously developed beam T-junction model, their results provided some strategies to improve the accuracy of beam-element-type approaches, taking into account the real junction stiffness [ 8 ].…”