scholarly journals Cellular Beams with Closely Spaced Web Openings – A Review of Analytical Calculation Models for Web-Post Buckling

2022 ◽  
Vol 16 (1) ◽  
pp. 213-230
Author(s):  
Przemysław Saternus
Keyword(s):  
Analytical Calculation ◽  
Web Openings ◽  
Post Buckling ◽  
Calculation Models

scholarly journals RESEARCH OF SELF-FORMATION NANOSTRUCTURES / NANODARINIŲ FORMAVIMOSI PROCESŲ TYRIMAS

2011 ◽  
Vol 3 (1) ◽  
pp. 59-62
Author(s):  
Romas Petrauskas
Keyword(s):  
Systematic Error ◽  
Analytical Calculation ◽  
Self Formation ◽  
Etching Duration ◽  
Calculation Models

Lateral etching processes for the modeling of the geometry of self-formation nanostructures with Silvaco TCAD Athena program are analyzed. Self-formation nanostructures is modeled with different mask selectivity values equal to 2, 10, 40 and 100 with respect to the etching layer, with the etching duration of 0–180 s. The etching rates are constant – 1.33 nm/s. The analysis of the dependence of the etching systematic error on its thickness has been carried out. The computer modeled results are close to the ones produced by means of the application of the analytical calculation models by other authors.

Web-post buckling of bolted castellated steel beam with octagonal web openings

2020 ◽  
Vol 164 ◽  
pp. 105794 ◽  
Author(s):  
Mei Liu ◽  
Mengdie Liang ◽  
Qijie Ma ◽  
Peijun Wang ◽  
Changwei Ma
Keyword(s):  
Steel Beam ◽  
Web Openings ◽  
Post Buckling

scholarly journals Analysis Beam-Column Cellular By Finite Element Method

10.29007/s1rd ◽  
2022 ◽  
Author(s):  
Minh Duc Nguyen ◽  
Thai Hien Nguyen
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Structural Elements ◽  
The Finite Element Method ◽  
Web Openings ◽  
Telephone Networks ◽  
The Past ◽  
Post Buckling ◽  
The Subject ◽  
Element Method

Nowadays in the construction of modem buildings, it is necessary to accommodate pipes and ducts necessary services, such as air conditioning, water supply, sewerage, electricity, computer networks, and telephone networks. Cellular members – steel I‐ shaped structural elements with circular web openings at regular intervals – have been used as beams for more than 35 years now. Although in the past already a large deal of research was performed into the subject of the behavior of cellular beams, almost no attention has been paid to the application of cellular members as columns. The column will be analyzed using the finite element method to calculate the critical load and compared with the Eurocode3 standard, web-post buckling, and frame using cellular member by FEM.

scholarly journals Experimental study of composite concrete cellular steel beams

2022 ◽  
Vol 961 (1) ◽  
pp. 012095
Author(s):  
Mustafa Kamil Abbas ◽  
Hayder Wafi Al_Thabhawee
Keyword(s):  
Concrete Beam ◽  
Ultimate Load ◽  
Steel Beams ◽  
Web Openings ◽  
Control Beam ◽  
Geometrical Properties ◽  
Shear Connectors ◽  
Depth Ratio ◽  
Post Buckling ◽  
Composite Steel

Abstract The main objective of this study is to compare the structural behavior of composite steel– concrete beams using cellular beams with and without steel ring stiffeners placed around the web openings. An IPE140 hot rolled I-section steel beam was used to create four specimens: one without openings (control beam); one without shear connectors (non-composite); a composite steel–concrete beam using a cellular beam without strengthening (CLB1); and a composite steel–concrete beam using a cellular beam (CLB4-R) with its openings strengthened by steel ring stiffeners with geometrical properties Br = 37mm and Tr = 5mm. CLB1 was fabricated with openings of 100mm diameter and a 1.23 expansion depth ratio, while CLB4-R was fabricated with openings of 130mm diameter, a 1.42 expansion depth ratio. Both beams were 1700mm in length with ten openings. The results of this experiment revealed that the loads applied to CLB1 and CLB4-R at deflection L/360 exceeded the load applied to the control specimen at the same deflection by 149.3% and 177.3%, respectively. The results revealed that the non-composite beam had an ultimate load 29% lower than that of the control beam. The ultimate load on CLB1 was 5.3% greater than that of the control beam, and failure occurred due to web-post buckling. While the ultimate load of the CLB4-R beam was 18.43% greater than that of the control beam, the Vierendeel mechanism was indicated as the failure mode.

Monte Carlo Modelling of Secondary Electron Yield from Rough Surfaces

1990 ◽  
Vol 48 (1) ◽  
pp. 422-423
Author(s):  
John C. Russ
Keyword(s):  
Monte Carlo ◽  
Energy Loss ◽  
Secondary Electron ◽  
Secondary Electron Emission ◽  
Analytical Calculation ◽  
Mean Free Path ◽  
Single Scattering ◽  
High Energy ◽  
Secondary Electron Yield ◽  
Electron Yield

Monte-Carlo programs are well recognized for their ability to model electron beam interactions with samples, and to incorporate boundary conditions such as compositional or surface variations which are difficult to handle analytically. This success has been especially powerful for modelling X-ray emission and the backscattering of high energy electrons. Secondary electron emission has proven to be somewhat more difficult, since the diffusion of the generated secondaries to the surface is strongly geometry dependent, and requires analytical calculations as well as material parameters. Modelling of secondary electron yield within a Monte-Carlo framework has been done using multiple scattering programs, but is not readily adapted to the moderately complex geometries associated with samples such as microelectronic devices, etc.This paper reports results using a different approach in which simplifying assumptions are made to permit direct and easy estimation of the secondary electron signal from samples of arbitrary complexity. The single-scattering program which performs the basic Monte-Carlo simulation (and is also used for backscattered electron and EBIC simulation) allows multiple regions to be defined within the sample, each with boundaries formed by a polygon of any number of sides. Each region may be given any elemental composition in atomic percent. In addition to the regions comprising the primary structure of the sample, a series of thin regions are defined along the surface(s) in which the total energy loss of the primary electrons is summed. This energy loss is assumed to be proportional to the generated secondary electron signal which would be emitted from the sample. The only adjustable variable is the thickness of the region, which plays the same role as the mean free path of the secondary electrons in an analytical calculation. This is treated as an empirical factor, similar in many respects to the λ and ε parameters in the Joy model.

A novel analytical calculation of magnetic field in the slotted air gap of spoke-type permanent-magnet machines using conformal mapping

2020 ◽  
pp. 1-15
Author(s):  
Jianqi Li ◽  
Yu Zhou ◽  
Jianying Li
Keyword(s):  
Magnetic Field ◽  
Conformal Mapping ◽  
Permanent Magnet ◽  
Flux Density ◽  
Analytical Method ◽  
Electromotive Force ◽  
Analytical Calculation ◽  
Air Gap ◽  
Permanent Magnet Machines ◽  
Peak Value

This paper presented a novel analytical method for calculating magnetic field in the slotted air gap of spoke-type permanent-magnet machines using conformal mapping. Firstly, flux density without slots and complex relative air-gap permeance of slotted air gap are derived from conformal transformation separately. Secondly, they are combined in order to obtain normalized flux density taking account into the slots effect. The finite element (FE) results confirmed the validity of the analytical method for predicting magnetic field and back electromotive force (BEMF) in the slotted air gap of spoke-type permanent-magnet machines. In comparison with FE result, the analytical solution yields higher peak value of cogging torque.

Sign in / Sign up

Export Citation Format

Share Document