Adaptive hpq finite element methods for the analysis of 3D-based models of complex structures. Part 1. Hierarchical modeling and approximations

Abstract This text sums up a research for the French Electric Company, EDF, which wants to know the influence of the temperature variability on the reliability of some of their boilers. These boilers are very complex structures whose behavior has to be modelized by the Finite Element Method, FEM. This work is an application of Finite Element Methods in a reliability context, that means the introduction of random data into a classical FEM, in order to determine the reliability of the structures. These random data may concern geometry, material characteristics of the structures or the loads the structure may carry. Then, it’s necessary to employ new methods to take into account these stochastic approaches and to obtain more efficient decision’s elements for a better control of the boilers.

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The Airplane Hangars of Pier Luigi Nervi: Digital and Scaled Models

Journal of the International Association for Shell and Spatial Structures ◽

10.20898/j.iass.2020.004 ◽

2020 ◽

Vol 61 (3) ◽

pp. 187-200

Author(s):

Giulio M. Barazzetta ◽

Emilio Mossa ◽

Carlo Poggi ◽

Marco Simoncelli

Keyword(s):

Finite Element ◽

Finite Element Methods ◽

Structural Models ◽

Structural Behavior ◽

Complex Structures ◽

The Past ◽

Starting Point ◽

Complete Study ◽

Scaled Models ◽

Work Done

The paper presents a complete study of the work done by Pier Luigi Nervi for the design and construction of a series of concrete hangars between 1935 and 1940. This research is enclosed in the framework of the exhibition entitled "Pier Luigi Nervi, il modello come strumento di progetto e costruzione" that gathers researches from Università degli Studi di Bologna, Università di Roma Tor Vergata and Politecnico di Milano. The exhibition was used as a starting point for a general discussion about the meaning of the logical passage that leads engineers and architects from physical scaled models to numerical structural models. The Politecnico di Milano contributed to re-writing the first experiences of Pier Luigi Nervi and Arturo Danusso in the structural modeling. Scaled models, nowadays substituted by finite element methods, were widely used in the past, for the understanding of the structural behavior of complex structures. Unfortunately, many of these masterpieces have been destroyed during the years (as happened to the two original models tested by Pier Luigi Nervi and reproduced for the exhibition). <br/> In the last part of the paper, based on numerical results, the structural behavior of these hangars is deeply discussed, underlining all the principal strengths and weaknesses of these complex structures.

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Combination of analytical and finite element methods to obtain acoustic fields in complex structures driven by piezoelectric multi-layered transducers

1997 IEEE Ultrasonics Symposium Proceedings. An International Symposium (Cat. No.97CH36118) ◽

10.1109/ultsym.1997.661738 ◽

2002 ◽

Author(s):

J.C. Adamowski ◽

M.Y. Matuda ◽

F. Buiochi ◽

C.M. Furukawa ◽

R.A. Sigelmann

Keyword(s):

Finite Element ◽

Finite Element Methods ◽

Complex Structures ◽

Acoustic Fields

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Adaptive hpq finite element methods for the analysis of 3D-based models of complex structures. Part 2. A posteriori error estimation

Computer Methods in Applied Mechanics and Engineering ◽

10.1016/j.cma.2013.08.018 ◽

2013 ◽

Vol 267 ◽

pp. 531-565 ◽

Cited By ~ 10

Author(s):

Grzegorz Zboinski

Keyword(s):

Finite Element ◽

Error Estimation ◽

Finite Element Methods ◽

Posteriori Error ◽

A Posteriori Error Estimation ◽

Complex Structures ◽

A Posteriori ◽

Posteriori Error Estimation ◽

A Posteriori Error

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Equilibrium Profile of Modern Belted Radial Ply Tires: Its Determination and Performance Benefits

Tire Science and Technology ◽

10.2346/tire.13.410203 ◽

2013 ◽

Vol 41 (2) ◽

pp. 127-151

Author(s):

Rudolf F. Bauer

Keyword(s):

Finite Element ◽

Aspect Ratio ◽

Finite Element Methods ◽

Mathematical Analysis ◽

Internal Stresses ◽

Stress Concentrations ◽

Equilibrium Profiles ◽

Equilibrium Profile ◽

And Performance ◽

Beneficial Property

ABSTRACT The benefits of a tire's equilibrium profile have been suggested by several authors in the published literature, and mathematical procedures were developed that represented well the behavior of bias ply tires. However, for modern belted radial ply tires, and particularly those with a lower aspect ratio, the tire constructions are much more complicated and pose new problems for a mathematical analysis. Solutions to these problems are presented in this paper, and for a modern radial touring tire the equilibrium profile was calculated together with the mold profile to produce such tires. Some construction modifications were then applied to these tires to render their profiles “nonequilibrium.” Finite element methods were used to analyze for stress concentrations and deformations within all tires that did or did not conform to equilibrium profiles. Finally, tires were built and tested to verify the predictions of these analyses. From the analysis of internal stresses and deformations on inflation and loading and from the actual tire tests, the superior durability of tires with an equilibrium profile was established, and hence it is concluded that an equilibrium profile is a beneficial property of modern belted radial ply tires.

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