The Effect of Weld Length on the Tension Capacity of Hollow Structural Section (HSS)

2020 ◽  
pp. 42-58
Keyword(s):  
Cross Section ◽  
Uniform Stress ◽  
Entire Cross Section ◽  
Design Strength ◽  
Minimum Requirement ◽  
Tension Member ◽  
Hollow Structural Section ◽  
Hollow Structural Sections ◽  
Tension Capacity ◽  
Steel Standard

The non-uniform stress distribution occurs in a tension member adjacent to a connection, in which all elements of the cross-section are not directly connected. This effect reduces the member’s design strength because the entire cross-section is not fully effective in the critical section’s location. That's why an experimental study has been done to investigate the effect of the weld length on the tension capacity, two specimens (hollow structural sections) have been tested by using Instron 8800 machine with two weld lengths, 46 mm and 56 mm. The 46 mm size is the minimum requirement of the sufficient size of the tension connection depending on United States Steel Standard. The Result proved that there has been too much effect on the connection carrying tension capacity. The result of the 46 mm weld length is about 155 KN and about 180 KN for the 56 mm weld length. While the ABAQUS simulation results were about 168 KN for the 46 mm weld length and about 172 KN for the 56 mm weld length.

Concrete-Filled Hollow Structural Sections. II: Flexural Members, Beam-Columns, Tension, and Shear

2021 ◽  
Author(s):  
Kyle Tousignant ◽  
Jeffrey Packer
Keyword(s):  
Reliability Analysis ◽  
Axial Compression ◽  
Cross Section ◽  
North American ◽  
Combined Loading ◽  
Flexural Members ◽  
Beam Columns ◽  
First Order ◽  
Hollow Structural Section ◽  
Hollow Structural Sections

This article reviews contemporary North American and international approaches to the design of concrete-filled hollow structural section (HSS) members for flexure, axial compression plus uniaxial bending, tension, and shear. Results from tests on concrete-filled HSS members under flexure and combined loading are compared to predicted strengths using current (CSA S16:19 and AISC 360-16) and recommended CSA S16 design equations (with limits of validity). A first-order reliability analysis of design provisions for flexure is performed in accordance with CSA S408-11, and recommendations are made for potential revision of CSA S16. Design examples are provided, and results are compared to the counterpart American code (AISC 360-16). This paper is Part II of a two-part series. Part I covers materials, cross-section classification, and concentrically loaded columns.

Calculation of the fire resistance of steel hollow structural section columns filled with plain concrete

1994 ◽  
Vol 21 (3) ◽  
pp. 382-385 ◽  
Author(s):  
T. T. Lie ◽  
D. C. Stringer
Keyword(s):  
Mathematical Models ◽  
Key Words ◽  
Fire Resistance ◽  
Experimental Studies ◽  
Plain Concrete ◽  
Building Codes ◽  
Aggregate Concrete ◽  
Parametric Studies ◽  
Hollow Structural Section ◽  
Hollow Structural Sections

Experimental studies were conducted to determine the fire resistance of circular and square hollow structural section columns filled with plain concrete. Mathematical models were developed and used to investigate the influence of important parameters that determine the fire resistance of these columns. The experimental and parametric studies provide information for the development of formulas for the calculation of the fire resistance of circular and square concentrically loaded columns filled with plain carbonate or siliceous aggregate concrete. Such formulas are suitable for incorporation into building codes. Key words: calculation, fire resistance, columns, concrete-filled, steel, hollow structural sections.

scholarly journals Evaluating Different Methods for Determining the Velocity-Dip Position over the Entire Cross Section and at the Centerline of a Rectangular Open Channel

Entropy ◽  
2020 ◽  
Vol 22 (6) ◽  
pp. 605
Author(s):  
Zhongfan Zhu ◽  
Pengfei Hei ◽  
Jie Dou ◽  
Dingzhi Peng
Keyword(s):  
Experimental Data ◽  
Cross Section ◽  
Shannon Entropy ◽  
Open Channel ◽  
Lateral Distribution ◽  
Tsallis Entropy ◽  
The Other ◽  
Deterministic Models ◽  
Entire Cross Section ◽  
General Index

The velocity profile of an open channel is an important research topic in the context of open channel hydraulics; in particular, the velocity-dip position has drawn the attention of hydraulic scientists. In this study, analytical expressions for the velocity-dip position over the entire cross section and at the centerline of a rectangular open channel are derived by adopting probability methods based on the Tsallis and general index entropy theories. Two kinds of derived entropy-based expressions have the same mathematical form as a function of the lateral distance from the sidewall of the channel or of the aspect ratio of the channel. Furthermore, for the velocity-dip position over the entire cross section of the rectangular open channel, the derived expressions are compared with each other, as well as with two existing deterministic models and the existing Shannon entropy-based expression, using fifteen experimental datasets from the literature. An error analysis shows that the model of Yang et al. and the Tsallis entropy-based expression predict the lateral distribution of the velocity-dip position better than the other proposed models. For the velocity-dip position at the centerline of the rectangular open channel, six existing conventional models, the derived Tsallis and general index entropy-based expressions, and the existing Shannon entropy-based models are tested against twenty-one experimental datasets from the literature. The results show that the model of Kundu and the Shannon entropy-based expression have superior prediction accuracy with respect to experimental data compared with other models. With the exception of these models, the Tsallis entropy-based expression has the highest correlation coefficient value and the lowest root mean square error value for experimental data among the other models. This study indicates that the Tsallis entropy could be a good addition to existing deterministic models for predicting the lateral distribution of the velocity-dip position of rectangular open channel flow. This work also shows the potential of entropy-based expressions, the Shannon entropy and the Tsallis entropy in particular, to predict the velocity-dip position at the centerline of both narrow and wide rectangular open channels.

Velocity Field and Energy Dissipation in Viscoplastic Flow in Tubes of Non-Circular Cross-Section

2014 ◽  
Author(s):  
Mario F. Letelier ◽  
Dennis A. Siginer ◽  
Felipe Godoy
Keyword(s):  
Energy Dissipation ◽  
Velocity Field ◽  
Yield Stress ◽  
Cross Section ◽  
Mechanical Energy ◽  
Longitudinal Velocity ◽  
Circular Cross Section ◽  
Viscoplastic Flow ◽  
Entire Cross Section ◽  
Cross Sectional

An analytical method for determining the velocity field, shear stress and energy dissipation in viscoplastic flow in non-circular straight tubes is presented. Bingham’s model of fluid is used for the case of tubes with several cross-sectional contours that can be arbitrarily chosen through a shape factor imposed in the solution for the longitudinal velocity. The analysis is extended to steady flow in tubes in which the cross-section contour exhibits sharp corners. In these cases three flow zones are distinguished: stagnant, non-zero deformation, and plug zones. The method provides the expressions for determining the boundaries and characteristics of those three zones for a wide variety of cross-section shapes. In particular the dynamics of plug-zones for large values of the yield stress and for contours that markedly differ from circumferences is analyzed. Energy dissipation is determined throughout the entire cross-section, so that the effect of shape on mechanical energy loss is assessed in terms of the yield stress and viscosity of the fluid. Some general expressions that help understand energy dissipation mechanisms are derived by using natural coordinates for the velocity field and related variables. These results draw on several recent works from other researchers and the present authors, which have highlighted the significant difficulty of determining the zones of zero deformation in viscoplastic flow when the related solid boundaries are not elementary.

Grain Refinement of Magnesium Alloy AZ31 under Torsion Extrusion with a Square-Hole Die

2010 ◽  
Vol 654-656 ◽  
pp. 711-714 ◽  
Author(s):  
Susumu Mizunuma ◽  
Takamichi Iizuka ◽  
Kazuhiro Mitsui ◽  
Hidehito Okumura ◽  
Masahide Kohzu
Keyword(s):  
Magnesium Alloy ◽  
Grain Refinement ◽  
Cross Section ◽  
Crystal Orientation ◽  
Electron Backscatter Diffraction ◽  
Entire Cross Section ◽  
Extrusion Axis ◽  
Alloy Az31 ◽  
Magnesium Alloy Az31 ◽  
Square Hole

Grain refinement and crystal orientation of magnesium alloy AZ31 under torsion extrusion with a square-hole die are investigated. The optimum temperature and ratio of the die rotation speed to the extrusion speed were clarified, resulting in uniformly distributed fine grains with sizes in the range 1- m over the entire cross section of the worked specimen. The crystal orientation of the specimen was determined by electron backscatter diffraction and compared with that of a conventionally extruded specimen. In the case of torsion extrusion, a very strong <0001> texture was observed along the extrusion axis, especially in the center region of the cross section. In contrast, the <0001> direction of many grains in the conventionally extruded specimen tended to be perpendicular to the extrusion axis.

Calibrating and Cross-Sectional Equalizing of the Sensitivity of Ultrasonic Phased Array Inspection of Welds

NDT World ◽  
2016 ◽  
Vol 19 (3) ◽  
pp. 17-27
Author(s):  
Нурматов ◽  
Islam Nurmatov ◽  
Лапидус ◽  
Aleks Lapidus ◽  
Пасси ◽  
...  
Keyword(s):  
Cross Section ◽  
Phased Array ◽  
Flaw Detector ◽  
Practical Implementation ◽  
Flat Bottom ◽  
Entire Cross Section ◽  
Cross Sectional ◽  
Common Reference ◽  
Amplitude Correction ◽  
Ultrasonic Phased Array

Introduction. The approach and practical implementation for the sensitivity calibration and its equalizing within entire insonified cross-section of the material have been presented in the article for 3 most common reference artificial reflectors, namely the flat bottom hole (FBH) situated at parallel to the weld bevel plane, the EDM notch (N), and the side drilled hole (SDH). The method. The issue of inhomogeneous sensitivity over cross-section covered through phased array (PA) sectorial scan plan is due to several factors, which are highlighted and explained. 5 of them are independent on the reference reflector’s shape. In addition the FBH and N reference reflectors are characterized by the strong dependency of the echo amplitude on the angle, under which the ultrasonic wave hits their surface (factor 6, which differs the FBH and N from the omnidirectional SDH). The approach for equalizing the sensitivity over sectorial-scan-insonified cross-section of the material for all types of reference reflectors has been proposed and explained. It is based on the ability of ultrasonic PA flaw detector to implement each pulsing-receiving cycle among the plurality of the scan-plan-forming set of focal laws with individually and independently settled gain and other key settings including Distance Amplitude Correction / Time Corrected Gain (DAC / TCG). The Sonotron NDT’s ISONIC Series PA instruments (ISONIC 3510, ISONIC 2010, and ISONIC 2009 UPA Scope) are featured with the said ability uniquely: in the said units the DAC / TCG mechanism is used purely for compensating the dependency of echo amplitude on the material travel distance while the feature of varying Gain per Focal Law is utilized just for the forming of easy-reproducible Angle Gain Compensation (AGC) plan. Both the DAC / TCG and AGC plans are created independently on each other with use of the same reference reflectors. The results. Combining of the independent DAC / TCG and AGC mechanisms for the first time ever provides the equalizing of the sensitivity for all types of reference reflectors independently on their X, Y position over the entire cross-section of the material — this is confirmed by a number of experimental results presented. Conclusion. At last the single group sectorial scan only becomes sufficient for the complete coverage of the whole cross-section of the weld. This allows reducing the dimensions of required PA probes and wedges in use and the width of the area for the scanning along the fusion line. And finally this increases the maximal possible speed of scanning along with reducing of the inspection cost.

Jet Interaction in Cross Flow: Experimental and Numerical Model

2014 ◽  
Author(s):  
Celso Almeida ◽  
António A. Nunes ◽  
Senhorinha Teixeira ◽  
José Carlos Teixeira ◽  
Pedro Lobarinhas
Keyword(s):  
Wind Tunnel ◽  
Cross Section ◽  
Large Scale ◽  
Cfd Simulation ◽  
Free Stream ◽  
Velocity Ratio ◽  
Cross Flow ◽  
Stream Velocity ◽  
Entire Cross Section ◽  
Injection Point

Ventilation of wide spaces often requires a correct mixing of a jet in a cross flow. The present paper describes the application of Computational Fluid Dynamics (CFD) to model the interaction of a free stream jet with a cross flow, taking into account temperature gradients between the two streams. The model uses the finite volume technique for solving the conservation equations of fluid: mass, momentum and energy. Buoyancy is described by the Boussinesq approximation. The convergence of the solution required a high mesh refinement in the region of flow interaction. The data were compared with experimental results obtained in a subsonic wind tunnel. The experiments were carried out along the 4.0 m long test section of a 1.4×0.8 low speed wind tunnel. The jets were injected at 90° through orifices 25 mm in diameter drawn from a plenum either at the same or higher temperature the free stream. The jet velocity to the free stream velocity ratio was set at 8 for a single jet and between 4 and 16 for multiple injections. Data include velocity, pressure and temperature. The results show that the injection of relatively small cross-flow rates can cause the development of large regions of interaction with the main flux, accompanied by the creation of large scale flow structures, which contribute effectively to rapid mixing of the two streams. A CFD simulation of temperature showed that a jet 30 diameters downstream (30D) is an extension of the plume covering almost half of the cross section and a good homogeneity, then the extension of the plume 120D which covers almost the entire cross section and an optimum mixing occurs. The CFD simulation temperature of 13 jets showed that a toroidal extension of the plume and a good homogenization as early as 30D downstream of the injection point, occurs.

Microstructural Characteristics of Mg-Zn-Y Alloy Containing Quasicrystal Phase under Pulsed Magnetic Field

2013 ◽  
Vol 456 ◽  
pp. 482-485 ◽  
Author(s):  
Lei Zhang ◽  
Quan Zhou ◽  
Kun Luo ◽  
Lin Yang
Keyword(s):  
Magnetic Field ◽  
Phase I ◽  
Cross Section ◽  
Pulsed Magnetic Field ◽  
Quasicrystalline Phase ◽  
Microstructural Characteristics ◽  
Entire Cross Section ◽  
Icosahedral Quasicrystalline Phase ◽  
Work Effect ◽  
Icosahedral Quasicrystalline

A novel pulsed magnetic field (PMF) processing has been employed for refining the microstructure of Mg-Zn-Y (Mg93Zn6Y) alloy in this work. Effect of PMF on the solidified microstructure of Mg93Zn6Y alloy containing icosahedral quasicrystalline phase (I-phase) was investigated. Experimental results show that solidified microstructure of Mg93Zn6Y alloy was significantly refined when the PMF was applied during solidification. I-phase in the entire cross-section of the billet changed from coarse, continuous and nonuniform morphology to uniform, fine and discontinuous morphology. In addition, primary α-Mg was significantly refined and also changed from developed dendrite to fine rosette. It was feasible to use PMF processing to refine the I-phase, because of its strong forced convection within the whole bulk melt.

scholarly journals Surface Magnetization Reversal of Wiegand Wire Measured by the Magneto-Optical Kerr Effect

Materials ◽  
2021 ◽  
Vol 14 (18) ◽  
pp. 5417
Author(s):  
Tomoaki Nakamura ◽  
Hiroki Tanaka ◽  
Tomofumi Horiuchi ◽  
Tsutomu Yamada ◽  
Yasushi Takemura
Keyword(s):  
Cross Section ◽  
Magnetization Reversal ◽  
Kerr Effect ◽  
Unique Feature ◽  
Optical Kerr Effect ◽  
Switching Field ◽  
Entire Cross Section ◽  
Significant Difference ◽  
Surface Magnetization ◽  
Magneto Optical Kerr Effect

The Wiegand wire is known to exhibit a unique feature of fast magnetization reversal in the magnetically soft region accompanied by a large Barkhausen jump. We clarified a significant difference between the magnetization reversals at the surface and at the entire cross section of a Wiegand wire. We conducted magnetization measurements based on the magneto-optical Kerr effect and applied conventional methods to determine the magnetization curves. The switching field of the magnetization reversal at the surface was greater than that at the initiation of a large Barkhausen jump. Our analysis suggests that the outer surface layer exhibits low coercivity.

scholarly journals Concrete-Filled Hollow Structural Sections. I: Materials, Cross-Section Classification, and Concentrically Loaded Columns

2021 ◽  
Author(s):  
Kyle Tousignant ◽  
Jeffrey Packer
Keyword(s):  
Reliability Analysis ◽  
Cross Section ◽  
Flexural Members ◽  
Beam Columns ◽  
First Order ◽  
Compression Members ◽  
Hollow Structural Sections

This paper reviews contemporary rules in CSA S16:19, AISC 360-16 and EN 1994-1-1 for concrete-filled hollow structural sections (HSS), covering materials, cross-section classification, and concentrically loaded columns. Results from 453 tests on axially compressed concrete-filled HSS members are compared to predicted strengths using current (CSA S16:19, AISC 360-16 and EN 1994-1-1) and recommended CSA S16 design equations (with limits of validity), and a first-order reliability analysis is performed in accordance with CSA S408-11. The recommendations herein are shown to maintain the current CSA S16:19 Clause 18.2 level of reliability for concrete-filled HSS compression members. Design examples are provided, and results are compared to the counterpart American code (AISC 360-16). This paper is Part I of a two-part series. Part II covers flexural members, beam-columns, tension and shear.

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