scholarly journals Analytical Method for the Bending Resistance of Slim Floor Beams with Asymmetric Double-T Steel Section under ISO Fire

2022 ◽  
Vol 12 (2) ◽  
pp. 574
Author(s):  
Diana Duma ◽  
Raul Zaharia ◽  
Dan Pintea ◽  
Ioan Both ◽  
Francois Hanus
Keyword(s):  
Cross Section ◽  
Concrete Slab ◽  
Numerical Procedure ◽  
Bending Resistance ◽  
Simplified Method ◽  
Different Types ◽  
Scope Of Application ◽  
Resistance Assessment ◽  
Common Shape ◽  
Steel Section

The slim floor beams, characterized by the steel profile embedded in the concrete slab, may be found in different configurations, based on the shape of the steel profile cross-section, which can vary from a rectangular to double-T section. While the most common shape used nowadays is the double-T cross-section, the Eurocodes do not provide a simplified method for the fire resistance assessment. The literature offers a simplified method for computation of bending resistance under elevated temperature, based on existing research on thermal models, and was validated for a particular type of slim floor beams (SFB). The current study extends the scope of application of this method, for different types of slim floor beam, which include an asymmetric double-T steel cross-section. The objective was reached through a numerical procedure, by analyzing 162 configurations subjected to four different fire requirements (R30, R60, R90, R120), resulting in a total of 648 analyses, performed with a validated numerical model in SAFIR software. The results in terms of bending resistance showed that the simplified method represents a strong tool for the fire design of slim floor beams.

scholarly journals Finite element analysis of concrete-encased steel composite columns with off-center steel section

2018 ◽  
Author(s):  
Jat Yuen Richard Liew ◽  
Binglin Lai ◽  
Shan Li
Keyword(s):  
Finite Element ◽  
Ultimate Strength ◽  
Cross Section ◽  
Fe Model ◽  
Top Down ◽  
Element Analysis ◽  
Composite Columns ◽  
Simplified Method ◽  
Steel Composite ◽  
Steel Section

Concrete encased steel composite columns have been widely used in high-rise buildings and top-down constructions owning to excellent load-carrying capacity and fire resistance. However, double symmetric composite section is rarely achieved due to the off-center eccentricity of steel kingpost, which is a common problem in top-down constructions. EN1994-1-1 (EC4) simplified method does not provide any explicit provisions for this kind of irregular composite columns, and many designers address this issue by reducing it into a symmetrical cross-section for ease of simple calculation. This paper presents a general method based on nonlinear finite element modelling software ABAQUS to analyze the ultimate strength behavior of concrete-encased composite columns with asymmetrically placed steel section. The accuracy of the FE model is verified against existing test results.   Parametric study is performed to further investigate the influence of steel section eccentricity on ultimate strength of stub columns under different loading conditions. A simplified method based on modification of EC4 design approach is developed to construct the moment-axial force interaction diagram. Accuracy of the proposed method is assessed by comparing the analytically predicted results with the numerical results. It is found that the proposed method can be adopted as a useful tool to predict the cross-section resistance of non-symmetrical concrete-encased steel composite columns. 

STRENX SECTION 900

Alloy Digest ◽  
2017 ◽  
Vol 66 (7) ◽  
Keyword(s):  
Fracture Toughness ◽  
High Strength ◽  
Bend Strength ◽  
Bend Channel ◽  
Cold Formed Steel ◽  
The Common ◽  
Hot Rolled ◽  
Common Shape ◽  
Minimum Yield ◽  
Steel Section

Abstract Strenx Section 900 is a cold-formed steel section made of hot-rolled, high-strength steel with a minimum yield strength of 900 MPa (131 ksi). Its high strength combined with naturally stiff form enables construction of stronger and lighter structures. The common shape is a U-bend channel. This datasheet provides information on composition, physical properties, tensile properties, and bend strength as well as fracture toughness. It also includes information on forming, machining, and joining. Filing Code: SA-792. Producer or source: SSAB Swedish Steel Inc..

scholarly journals Parametric optimization of the cross-section and shape of the longitudinal member in frontal impact

2019 ◽  
Vol 140 ◽  
pp. 02013
Author(s):  
Dmitry Bogdanov ◽  
Yury Boldyrev ◽  
Pavel Cvetkov ◽  
Oleg Klyavin ◽  
Ilya Davydov ◽  
...  
Keyword(s):  
Cross Section ◽  
Parametric Optimization ◽  
Numerical Procedure ◽  
Software Systems ◽  
Engineering Analysis ◽  
Frontal Impact ◽  
Mathematical Statement ◽  
Analysis And Design ◽  
Optimization Task ◽  
Python Programming

The article considers the problem of optimal design of car body elements (longitudinal members) according to the chosen criteria. Both the questions of formulation of the optimization task and individual problems of its solution are studied. The mathematical statement of the problem is considered. Thus, the most attention is given to consideration of realisation of used numerical procedure of optimization. The system of numerical calculations is based on the most widely spread software systems for engineering analysis and design. The developed scripts on Python programming language are briefly considered. Results of optimization of longitudinal members of the car are given.

The study of neutron capture processes in AlN nanoparticles

2021 ◽  
pp. 2150127
Author(s):  
T. G. Naghiyev
Keyword(s):  
Computer Modeling ◽  
Cross Section ◽  
Neutron Capture ◽  
Absorption Cross Section ◽  
Effective Cross Section ◽  
Absorption Cross ◽  
Effective Absorption ◽  
Different Types ◽  
N Isotopes

The neutron capture processes in the AlN nanoparticles were investigated by computer modeling. Neutrons absorption were separately investigated for aluminum (Al) and nitrogen (N) atoms in the AlN nanoparticles. The modeling was performed separately for each stable Al and N isotopes, because the effective absorption cross-section of different types of isotopes of Al and N atoms is different. Moreover, effective cross-section spectra of neutron capture for aluminum and nitrogen atoms were comparatively investigated.

scholarly journals Bhabha scattering in very special relativity at finite temperature

2020 ◽  
Vol 80 (8) ◽  
Author(s):  
Alesandro Ferreira dos Santos ◽  
Faqir C. Khanna
Keyword(s):  
Differential Cross Section ◽  
Special Relativity ◽  
Cross Section ◽  
Differential Cross ◽  
Local Form ◽  
Bhabha Scattering ◽  
Thermo Field Dynamics ◽  
Different Types ◽  
Non Local ◽  
Very Special Relativity

Abstract In this paper the differential cross section for Bhabha scattering in the very special relativity (VSR) framework is calculated. The main characteristic of the VSR is to modify the gauge invariance. This leads to different types of interactions appearing in a non-local form. In addition, using the Thermo Field Dynamics formalism, thermal corrections for the differential cross section of Bhabha scattering in VSR framework are obtained.

scholarly journals Prevalence of Gastrointestinal Helminth Infections in Indigenous Chickens of Selected Areas of Barisal District, Bangladesh

2014 ◽  
Vol 12 (2) ◽  
pp. 135-139 ◽  
Author(s):  
MN Alam ◽  
M Mostofa ◽  
MAHNA Khan ◽  
MA Alim ◽  
AKMA Rahman ◽  
...  
Keyword(s):  
Cross Section ◽  
Helminth Parasites ◽  
Ascaridia Galli ◽  
Routine Examination ◽  
Pathological Lesions ◽  
Heterakis Gallinarum ◽  
Indigenous Chickens ◽  
Gastrointestinal Helminth ◽  
Helminth Infections ◽  
Different Types

The prevalence of gastrointestinal helminth infections and the gross pathological lesions produced by them were studied from February 2012 to January 2013 in the Department of Pharmacology of Bangladesh Agricultural University, Mymensingh. In this study, a total of 320 indigenous chickens aged ranging from 2 to 4 months were examined to identify the different types of gastrointestinal helminth infections in indigenous chickens. During routine examination, six species of helminth parasites were recorded, of which five species of nematodes such as Ascaridia galli, Heterakis gallinarum, Capillaria spp, Acuaria hamulosa and Dispharynx spiralis; and one species was cestode called Raillietina tetragona. The highest prevalence was observed for Ascaridia galli (41.56%) followed in descending order by Raillietina tetragona (19.68%), Heterakis gallinarum (15.62%), Acuaria hamulosa (8.75%), Capillaria spp. (4.68% ) and Disopharinx spiralis (1.56%). The gross pathological lesions were observed in case of Acuaria hamulosa and Heterakis gallinarum infection. In case of Acuaria hamulosa infection keratinization of gizzard mucosa and cross section of adult Acuaria hamulosa were seen along with marked infiltration of neutrophils. The results of this study suggest that both nematodes and cestodes are highly prevalent in indigenous chickens in the studied area.DOI: http://dx.doi.org/10.3329/bjvm.v12i2.21275 Bangl. J. Vet. Med. (2014). 12 (2): 135-139 

scholarly journals Effects of Using Channelling Devices to Increase Efficiency of Hydrokinetic Devices

2015 ◽  
Vol 52 (2) ◽  
pp. 3-12
Author(s):  
A. Kalnacs ◽  
J. Kalnacs ◽  
A. Mutule ◽  
V. Entins
Keyword(s):  
Flow Control ◽  
Flow Velocity ◽  
Cross Section ◽  
Power Output ◽  
High Importance ◽  
Different Types ◽  
The Cross ◽  
Increase Efficiency ◽  
Flow Velocities

Abstract In the rivers of Latvia and of many other countries the flow velocity in the places that are most suitable for installation of hydrokinetic devices is 0.4 to 0.9 m/s. In a stream or a river the hydrokinetic devices can reach full efficiency starting from about twice higher flow velocities. It is advisable to at least double this velocity thus increasing the efficiency and power output of the hydrokinetic devices installed in such places. Since Latvia has abundance of slow rivers and almost none are fast, research in this field is of high importance. Diversified technical methods are known that allow increasing substantially the efficiency of hydrokinetic devices. These methods include the use of diffusers, concentrators, different types of other channelling devices and means of flow control. Desirable effects are achieved through changing the cross-section and/or direction of a flow, its pressure, minimizing the turbulence, etc. This work substantiates the use of such devices for increasing the efficiency of hydrokinetic devices. A method is proposed for evaluation of the effects on power output gained owing to the use of channelling devices. Results show that the efficiency of hydrokinetic devices can be increased by at least 110%.

Theoretic-Strength Concept of a Model Describing the Destruction of the Corner Part of a Slab-Column Structure

2015 ◽  
Vol 240 ◽  
pp. 225-231 ◽  
Author(s):  
Mirosław Wieczorek
Keyword(s):  
Reinforced Concrete ◽  
Cross Section ◽  
Laboratory Tests ◽  
Concrete Slab ◽  
Load Capacity ◽  
Limit Load ◽  
Traditional Theory ◽  
Load Step ◽  
Reinforced Concrete Slab ◽  
Column Structure

The paper presents a proposed theoretical-strength destruction model of the corner of a slab-column structure at 1:2 scale. The theoretical destruction model was developed on the basis of laboratory tests of a reinforced concrete slab with the dimensions 4000×4000×100 mm. The assumptions of the proposed theoretical model were based on a traditional theory of behaviour of reinforced concrete constructions. The method for calculating the strength of reinforced concrete sections is based on interaction graphs of the load capacity NRd, MRd,x and MRd,y. The calculation method takes into account the influence of changes in the shape of the cross-section of the analysed element on its limit load capacity in every load step.

scholarly journals Thermal Stresses in the Wall Connections of Cast Grate Structures

2016 ◽  
Vol 16 (4) ◽  
pp. 11-16 ◽  
Author(s):  
A. Bajwoluk ◽  
P. Gutowski
Keyword(s):  
Heat Treatment ◽  
Cross Section ◽  
Hot Spots ◽  
Thermal Stresses ◽  
Cooling Process ◽  
Temperature Variations ◽  
Temperature Changes ◽  
Different Types ◽  
The Difference ◽  
The Impact

Abstract The purpose of this study was to establish a relationship between the type of wall connection used in the cast grates, which are part of the equipment operating in furnaces for heat treatment and thermal-chemical treatment, and stresses generated in these grates during the process of rapid cooling. The places where the grate walls are connected to each other are usually characterized by the thickness larger than the remaining parts of walls. Temperature variations in those places are responsible for the formation of hot spots, and in the hot spots temperature changes much more slowly. The type of wall connection shapes the temperature gradient in the joint cross-section, and hence also the value of thermal stresses generated during cooling. In this study, five different designs of the grates were compared; the difference in them was the type of the designed wall connection. The following design variants were adopted in the studies: X connections with and without holes, T connections with and without technological recesses, and R (ring) connection. Numerical analysis was performed to examine how the distribution of temperature changes in the initial phases of the cooling process. The obtained results served next as a tool in studies of the stress distribution in individual structures. The analysis were carried out by FEM in Midas NFX 2014 software. Based on the results obtained, the conclusions were drawn about the impact of different types of wall connections on the formation of thermal stresses in cast grates.

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