Finite element modeling is employed to study the behavior and characteristics of flush end plate, bolted connections. To investigate the failure mechanism and non-linear behavior of the connections a 3D model is created and analyzed using non-linear material models and contacts between components of the connection. The paper shows the good agreement between the experimental and numerical results.
Finite element meshes are the basic data structures of engineering analyses and simulations. Unfortunately many different kinds of finite element mesh formats exist. These different formats can make it difficult to handle the meshes in several aspects, for example when the same simulation should be checked and validated by another program or to preserve these data for long term. For both cases the conversion of finite element meshes can be a solution, however there is another problem in this case, that the size of the meshes are constantly increasing and meshes with over a million elements are commonly used nowadays. This paper would like to discuss how these large meshes can be converted in a parallel fashion and it also presents how this method can be used in the preservation and storage of finite element meshes.
Laboratory and numerical experiments have been carried out to investigate the pullout phenomenon of a bolt from a steel plate. The experiments show two distinctly different failure modes and a transition failure mode. The failure modes mainly depend on the thickness of the steel plate for the given diameter of screw. The experiments are numerically simulated and the obtained numerical results are compared with those obtained by the laboratory-testing program.
Authors:Miklos Iványi, Miklos Iványi, and Peter Iványi
According to the different designs of steel frames the connections can be characterized by different elastic, plastic and ductile behaviors. The most well-known connection type is the end-plate, bolted connection when a beam connected to the strong axis of a column. The design and analysis of this type of connection is discussed in detail in the EC3 Standard (1.8). On the other hand in the case of steel frames it is a common solution to connect a beam to the weak axis of a column or 3D connections and unfortunately current design standards do not contain solutions for these cases.During the current research project the elastic, plastic and ductile behaviour of beams connected to the strong and weak axis of columns have been investigated. The experimental program have investigated three connections: Type A is a connection without column web stiffeners, Type B is a connection with column web stiffeners and Type C is a connection using U beams to connect beams to the column.
The generation of printable shellcode is an important computer security research area. The original idea of the printable shellcode generation was to write a binary, executable code in a way that the generated byte code contains only bytes that are represented by the English letters, numbers and punctuation characters. In this way unfortunately only a limited number of CPU instructions can be used. In the originally published paper a small decoder is written with instructions represented by printable characters and the shellcode is decoded on the stack to be executed later. This paper, however describes a proof of concept project, which converts the source code of a full assembly program or shellcode to a new source code, whose compiled binary code contains only printable characters. The paper also presents new, printable character implementation of some CPU instructions.
Authors:Jeno Balogh, Massimo Fragiacomo, Richard Gutkowski, Rebecca Atadero, and Peter Ivanyi
In a wood-concrete composite structural member the wood layer overlapped by the concrete layer are interconnected to prevent the relative slip. In this research notched shear-key interlayer connections were used. A problem with using these novel composite members in bridges is that the fatigue behavior of the composite member is not well known. This paper presents an S-N curve for fatigue verification of notched wood-concrete connections based on static and low-to-high-cycle repeated loading tests on fourteen composite beam specimens. The points on the S-N curve were determined for three levels of the maximum load as a function of the average static failure load.
Authors:Réka Sárközi, Péter Iványi, and Attila Béla Széll
This paper describes the adaptation of the formex configuration processing to the computer program Grasshopper 3D and focuses on the applied mathematical solutions. Formex algebra is a mathematical system, primarily used for planning structural systems like truss-grid domes and vaults, together with the programming language Formian. The goal of the research is to allow architects to plan truss-grid structures easily with parametric design tools based on the versatile formex algebra mathematical system. To produce regular structures, coordinate system transformations are used. Owing to the abilities of the parametric design software, it is possible to apply further modifications on the structures and gain special forms. The paper covers the basic dome types, and it introduces additional dome-based structures using special coordinate-system solutions based on a spherical coordinate system, vault structures and their modifications based on a cylindrical coordinate system and circular structures and their modifications based on polar coordinates. Moreover two rotational grid tools are introduced, which uses coordinate system transformations on a unique way to create surfaces of revolutions based on the given generating curve and create grid structures on these surfaces. It also describes the solution technique to implement the triangular grid version of every one of these tools based on diamatic domes. The adaptation of formex algebra and the parametric workflow of Grasshopper together give the possibility of quick and easy design and optimization of special truss-grid domes.
Authors:Réka Sárközi, Péter Iványi, and Attila Béla Széll
The main objective of this paper is to classify the techniques of parametric design, and to make the existing classification system more exact. The previously created classification was based on shape and logical aspects, which granted a good approach for parametric design techniques and helped providing an overview. However this system, for the sake of scientific precision, needed further darification at points. In this paper a more precise classification is shown, which is based on the interpretation of patterns as graphs. This enables their topology to be studied in a more exact, mathematical way.