The structural behavior of castellated beam with shape variation using finite element methods

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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Numerical analysis of two pile caps with sockets embedded, subject the eccentric compression load

Revista IBRACON de Estruturas e Materiais ◽

10.1590/s1983-41952013000300007 ◽

2013 ◽

Vol 6 (3) ◽

pp. 436-474

Author(s):

R. G. Delalibera ◽

J. S. Giongo

Keyword(s):

Finite Element ◽

Numerical Analysis ◽

Numerical Simulations ◽

Finite Element Methods ◽

Normal Load ◽

Structural Behavior ◽

Compression Load ◽

Linear Behavior ◽

Non Linear ◽

Pile Caps

The structural behavior of pile caps with sockets embedded is influenced by interface of column-socket, which can be smooth or rough. With intent to analyze the behavior of two pile caps with embedded socket, considering the friction between the column and the socket, with eccentric normal load, the numerical simulations were carried out, using a program based on the Finite Element Methods (FEM). In the numerical analysis the non-linear behavior of materials was considered, also the friction between the column and the socket. It was considered perfect bond between the reinforcement and the concrete around. It was observed that the embedded length is preponderant factor in the structural behavior of the analyzed element.

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Composite Mechanics for Engine Structures

Volume 5: Manufacturing Materials and Metallurgy; Ceramics; Structures and Dynamics; Controls, Diagnostics and Instrumentation; Process Industries; General ◽

10.1115/87-gt-88 ◽

1987 ◽

Author(s):

Christos C. Chamis

Keyword(s):

Finite Element ◽

Dynamic Response ◽

Finite Element Methods ◽

Damage Tolerance ◽

Computational Simulation ◽

Research Center ◽

Structural Behavior ◽

Structural Dynamic ◽

Research Activities ◽

Composite Mechanics

Recent research activities/accomplishments at Lewis Research Center on composite mechanics for engine structures are reviewed in summary form. The activities mainly focused on developing procedures for the computational simulation of composite intrinsic and structural behavior. The computational simulation encompasses all aspects of composite mechanics, advanced 3-D finite element methods, damage tolerance, composite structural/dynamic response and structural tailoring/optimization.

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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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