Structural parameters analysis for tapered steel section with perforation: effect of shear buckling behaviour

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Fatimah De’nan ◽  
Nor Salwani Hashim ◽  
Xing Yong Sua ◽  
Pui Yee Lock
Keyword(s):  
Structural Parameters ◽  
Bending Moment ◽  
Building Design ◽  
Buckling Load ◽  
Deformation Pattern ◽  
Element Analysis ◽  
Cross Sectional ◽  
Content Type ◽  
Shear Buckling ◽  
Steel Section

Purpose Due to economic development, tapered members are commonly applied in steel frames, namely, industrial halls, warehouses, exhibition centres, etc. In the design of cantilever steel beam structures in cities building design, tapering is introduced at the web profile to achieve utmost economy and suit the bending moment distributions. The cross-sectional shape of the beam is varied linearly to the moment gradient to achieve the target of higher efficiency with lower cost. Design/methodology/approach The shear deformation pattern and efficiency of the tapered steel section with perforation were investigated using finite element analysis. In addition, I-beam with web opening is studied numerically via LUSAS software for different parameters of tapering ratio, perforation shape and perforation size and perforation layout. Findings The highest contributing parameters for the highest shear buckling capacity and efficiency of the section were due to the small opening size and tapering ratio. Whilst the variation of perforation layout and spacing give a major effect on the shear strength and efficiency of the tapered steel section with perforation. Besides that, the highest efficiency model is found when the section is designed with 0.4 D diamond perforation in Layout 3 under a tapering ratio of 0.3. The critical shear buckling load and efficiency is reduced 14.39% and 13.91%, respectively, when perforations are added onto the tapered steel sections. Originality/value The tapered steel section with perforation has lower critical shear buckling load and efficiency compared to the tapered section without perforation but obtains a higher critical shear buckling load and efficiency compared to the uniform section without perforation.

scholarly journals Shear Performance of Optimized-Section Precast Slab with Tapered Cross Section

2018 ◽  
Vol 11 (1) ◽  
pp. 163 ◽  
Author(s):  
Hyunjin Ju ◽  
Sun-Jin Han ◽  
Hyo-Eun Joo ◽  
Hae-Chang Cho ◽  
Kang Kim ◽  
...  
Keyword(s):  
Cross Section ◽  
Design Method ◽  
Precast Concrete ◽  
Bending Moment ◽  
Shear Behaviour ◽  
Element Analysis ◽  
Cross Sectional ◽  
Shear Design ◽  
Shear Performance ◽  
And Performance

The optimized-section precast slab (OPS) is a half precast concrete (PC) slab that highlights structural aesthetics while reducing the quantity of materials by means of an efficient cross-sectional configuration considering the distribution of a bending moment. However, since a tapered cross section where the locations of the top and bottom flanges change is formed at the end of the member, stress concentration occurs near the tapered cross section because of the shear force and thus the surrounding region of the tapered cross section may become unintentionally vulnerable. Therefore, in this study, experimental and numerical research was carried out to examine the shear behaviour characteristics and performance of the OPS with a tapered cross section. Shear tests were conducted on a total of eight OPS specimens, with the inclination angle of the tapered cross section, the presence of topping concrete and the amount of shear reinforcement as the main test variables and a reasonable shear-design method for the OPS members was proposed by means of a detailed analysis based on design code and finite-element analysis.

Development of a stream function-upper bound analysis applicable to the process of plate rolling

2016 ◽  
Vol 12 (2) ◽  
pp. 254-274 ◽  
Author(s):  
Amir Asgharzadeh ◽  
Siamak Serajzadeh
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Velocity Field ◽  
Stream Function ◽  
Upper Bound ◽  
Deformation Zone ◽  
Deformation Pattern ◽  
Element Analysis ◽  
Content Type ◽  
Plate Rolling

Purpose – The purpose of this paper is to develop a mathematical solution to estimate the deformation pattern and required power in cold plate rolling using coupled stream function method and upper bound theorem. Design/methodology/approach – In the first place, an admissible velocity field and the geometry of deformation zone are derived from a new stream function. Then, the optimum velocity field is obtained by minimizing the corresponding power function. Also, to calculate the adiabatic heating during high speed rolling operations, a two-dimensional conduction-convection problem is sequentially coupled with the mechanical model. To verify the predictions, rolling experiments on aluminum plates are conducted and also, a finite element analysis is performed by Abaqus/Explicit. The predicted deformation zone is then compared with the experimentally measured region as well as with the results of the finite element analysis. Findings – The results show that the predicted deformation zone and the temperature distribution fit reasonably with the experimental data while much lower computational cost needs comparing to the fully finite element analysis. Originality/value – A new stream function is proposed to properly describe the velocity field and deformation pattern during plate rolling considering the neutral point. Furthermore, the employed algorithm can be simply coupled with the thermal finite element analysis.

scholarly journals Analisis Numerik Kuat Lentur Balok Support Beam Curve Tile Beton Semi Pracetak Dengan Variasi Panjang Bentangan

2020 ◽  
Vol 8 (2) ◽  
pp. 61-69
Author(s):  
Yoga Ornando ◽  
Ismeddiyanto ◽  
Iskandar Romey Sitompul
Keyword(s):  
Precast Concrete ◽  
Bending Moment ◽  
Maximum Load ◽  
Crack Pattern ◽  
Beam Length ◽  
Pure Bending ◽  
Element Analysis ◽  
Cross Sectional ◽  
Cross Sectional Dimension ◽  
The Cross

Semi precast slab is a combination of precast concrete which consist of the support beam and curve tile with the cast in place concrete. During the working process, support beam will support the entire load until the slab becomes solid. The study aims to identify the effect of using variations of support beam length towards deflection-load relationship, moment-curvature, crack pattern and cross-sectional dimensions caused by pure bending moments with the same maximum load. The variations of the support beam length are L = 3000 mm, L = 4000 mm, L = 5000 mm and L = 6000 mm which can affect the cross-sectional dimensions of the support beam. The method used in this study was the numerical method by using Abaqus 6.14 CAE software. Abaqus is one of the finite element analysis (FEA) programs to model and analysis the elements of the structure. The loading applied was an axial load which has increased until the support beam failed. The numerical analysis results are the increase of cross section dimension as the increasing of support beam length. The cross-sectional dimension are 100 mm x 60 mm; 110 mm x 65 mm; 110 mm x 70 mm; and 115 mm x 75 mm. The maximum load (Pmaks) was relative same while the support beam length increased are 1,52 kN; 1,53 kN; 1,53 kN and 1,55 kN. The collapse pattern on the support beam was a pure bending crack at the most significant bending moment region. The crack pattern showed the crack on the pull side of the beam in the direction of the stirrups.Semi precast slab is a combination of precast concrete which consist of the support beam and curve tile with the cast in place concrete. During the working process, support beam will support the entire load until the slab becomes solid. The study aims to identify the effect of using variations of support beam length towards deflection-load relationship, moment-curvature, crack pattern and cross-sectional dimensions caused by pure bending moments with the same maximum load. The variations of the support beam length are L = 3000 mm, L = 4000 mm, L = 5000 mm and L = 6000 mm which can affect the cross-sectional dimensions of the support beam. The method used in this study was the numerical method by using Abaqus 6.14 CAE software. Abaqus is one of the finite element analysis (FEA) programs to model and analysis the elements of the structure. The loading applied was an axial load which has increased until the support beam failed. The numerical analysis results are the increase of cross section dimension as the increasing of support beam length. The cross-sectional dimension are 100 mm x 60 mm; 110 mm x 65 mm; 110 mm x 70 mm; and 115 mm x 75 mm. The maximum load (Pmaks) was relative same while the support beam length increased are 1,52 kN; 1,53 kN; 1,53 kN and 1,55 kN. The collapse pattern on the support beam was a pure bending crack at the most significant bending moment region. The crack pattern showed the crack on the pull side of the beam in the direction of the stirrups.

scholarly journals Numerical Study on Plastic Strain Distributions and Mechanical Behaviour of a Tube under Bending

Inventions ◽  
2022 ◽  
Vol 7 (1) ◽  
pp. 9
Author(s):  
Chiemela Victor Amaechi ◽  
Emmanuel Folarin Adefuye ◽  
Abiodun Kolawole Oyetunji ◽  
Idris Ahmed Ja’e ◽  
Ibitoye Adelusi ◽  
...  
Keyword(s):  
Plastic Strain ◽  
Mechanical Behaviour ◽  
Numerical Study ◽  
Bending Moment ◽  
Thickness Effect ◽  
Element Analysis ◽  
Cross Sectional ◽  
Linear Elastic ◽  
The Finite Element Analysis ◽  
Pipe Bending

Tubular pipe structures have been used in various applications—domestic, aviation, marine, manufacturing and material testing. The applications of tubular pipes have been considered greatly in the installation of tubular pipes, marine risers and pipe bending. For the investigation of plastic strains and the mechanical behaviour of a tube under bending, considerations were made utilising an exponent model with assumptions on the plane strain. The bending moment, wall thickness effect, cross-sectional distribution, stresses during bending and neutral layer boundaries were all presented as necessary theoretical formulations on the physics of tubular pipe bending. This model was based on the analytical and numerical investigation. In principle, the application can be observed as the spooling of pipes, bending of pipes and reeling. Comparisons were made on two models developed on the finite element analysis in Simscale OpenFEA, namely the linear-elastic and the elasto-plastic models. This study presents visualization profiles using plastic strain to assess its effect on the tubular pipes. This can increase due to the limitation of plastic deformation on the composite materials selected.

Quantification of elastic stresses for structurally distorted 90° very thin-walled pipe bends under in-plane bending

2020 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Krishna LA ◽  
Veerappan AR ◽  
Shanmugam S
Keyword(s):  
Elastic Stress ◽  
Bending Moment ◽  
Accurate Estimation ◽  
Membrane Stress ◽  
Creep Failure ◽  
Cross Sectional ◽  
Content Type ◽  
Elastic Stresses ◽  
Thin Walled ◽  
Plane Bending

PurposeElastic stress solutions are required in the field of fracture mechanics and the analysis of creep failure. The published precise elastic solutions are not addressing the influence of the manufacturing process induced, inevitable cross sectional deviations called ovality and thinning. The influence of ovality on plastic limit and collapse loads are reported in literature. Hence, it is important to study the combined effect of ovality and thinning on elastic stresses of bends.Design/methodology/approachThis paper relies on elastic finite element evolutions of stress components– longitudinal membrane stress, longitudinal bending stress, circumferential membrane stress and circumferential bending stresses. Based on the results, the coefficients for the equations are also obtained through the regression analysis.FindingsNew analytical solutions are prescribed to estimate the elastic stresses at the mid-section of the 90° very thin-walled bend with ovality and thinning, when subjected to in-plane bending moment. The ovality has significant influence on elastic stress whereas the thinning is not so. The proposed equations give an accurate estimation of elastic stresses at the mid-section of the bend with the incorporation of the parameters, namely R/rm, rm/t and ovality.Research limitations/implicationsThe influence of shape imperfections, namely ovality and thinning on elastic stress of 90° very thin-walled bends having rm/t > 20, subject to in-plane bending moment is proposed.Originality/valueThe influence of shape imperfections, namely ovality and thinning, on elastic stress of 90° very thin-walled bends with rm/t > 20, subject to in-plane bending moment is proposed.

scholarly journals Analysis of pressure-bearing performance and optimization of structural parameters of the slip in a compression packer

2019 ◽  
Vol 103 (1) ◽  
pp. 003685041988110 ◽  
Author(s):  
Yang Tang ◽  
Peng Sun ◽  
Guorong Wang ◽  
Wang Li
Keyword(s):  
Structural Parameters ◽  
Bending Moment ◽  
Test Method ◽  
Analysis Model ◽  
Element Analysis ◽  
Orthogonal Test Method ◽  
Downhole Tool ◽  
Casing Pressure

In drilling and completion operations, a packer is a downhole tool to seal the annular space between various sizes of string and borehole. As a key component of packer, slip plays a role of fixed support in the process of setting, thus ensuring a long-term stable sealing of the packer. Aiming at the problem of damage caused by casing pressure on the slip after setting, based on the stress analysis of slip during setting, the slip material with hardness lower than casing was selected, and its finite element analysis model was established. Then, the pressure-bearing law of the slip teeth under three tooth parameters was analyzed. The results of analysis were as follows. With the increase of the number of slips or the distance between teeth or tooth top angle, the strain of slips decreased, but the bending moment of slips increased. At the same time, orthogonal test method was used to optimize the parameters of the slips. The conclusion is that the tooth top angle is 90 degrees, the distance between teeth is 6 mm and the number of teeth is 16, which is the best combination of compressive effect. It will provide a reference for improving the long-term effectiveness of the packer seal in drilling and completion engineering.

Combined effect of shape distortion and bend angle on collapse load of pipe bends under in-plane closing bending moment and internal pressure

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
R. Silambarasan ◽  
V.R. Veerappan ◽  
S. Shanmugam
Keyword(s):  
Internal Pressure ◽  
Bending Moment ◽  
Combined Effect ◽  
Bend Angle ◽  
Collapse Load ◽  
Shape Distortion ◽  
Element Analysis ◽  
Pipe Bend ◽  
Content Type ◽  
Bend Angles

Purpose The purpose of this paper is to quantify the combined effect of shape distortion and bend angle on the collapse loads of pipe bends exposed to internal pressure and in-plane closing bending moment. Non-linear finite element analysis with large displacement theory was performed considering the pipe bend material to be elastic perfectly plastic. Design/methodology/approach One half of the pipe bend model was built in ABAQUS. Shape distortion, namely, ovality (Co) and thinning (Ct), were each varied from 0% to 20% in steps of 5% and bend angle was varied from 30° to 180° in steps of 30°. Findings The findings show that ovality has a significant impact on collapse load. The effect of ovality decreases with an increase in bend angle for small thickness. The opposite effect was observed for large thickness pipe bends. The influence of ovality was more for higher bend angles. Ovality impact was almost negligible at certain internal pressure denoted as nullifying point (NP). The latter increased with an increase in pipe bend thickness and decreased with increase in pipe bend radius. For small bend angles one NP was observed where ovality impact is negligible and beyond this point the ovality effect increased. Two NPs were observed for large bend angles and ovality effect was maximum between the two NPs. Thinning yielded a minimal effect on collapse load except for small bend angles and bend radii. The influence of internal pressure on thinning was also negligible. Originality/value Influence of shape distortions and bend angle on collapse load of pipe bend exposed to internal pressure and in-plane closing bending has been not revealed in existing literature.

Financial distress determinants among SMEs: empirical evidence from Sweden

2020 ◽  
Vol 47 (3) ◽  
pp. 547-560 ◽  
Author(s):  
Darush Yazdanfar ◽  
Peter Öhman
Keyword(s):  
Financial Crisis ◽  
Financial Distress ◽  
Large Scale ◽  
Global Financial Crisis ◽  
Binary Logistic Regression ◽  
Data Availability ◽  
Cross Sectional ◽  
Data Set ◽  
Content Type ◽  
The Global Financial Crisis

PurposeThe purpose of this study is to empirically investigate determinants of financial distress among small and medium-sized enterprises (SMEs) during the global financial crisis and post-crisis periods.Design/methodology/approachSeveral statistical methods, including multiple binary logistic regression, were used to analyse a longitudinal cross-sectional panel data set of 3,865 Swedish SMEs operating in five industries over the 2008–2015 period.FindingsThe results suggest that financial distress is influenced by macroeconomic conditions (i.e. the global financial crisis) and, in particular, by various firm-specific characteristics (i.e. performance, financial leverage and financial distress in previous year). However, firm size and industry affiliation have no significant relationship with financial distress.Research limitationsDue to data availability, this study is limited to a sample of Swedish SMEs in five industries covering eight years. Further research could examine the generalizability of these findings by investigating other firms operating in other industries and other countries.Originality/valueThis study is the first to examine determinants of financial distress among SMEs operating in Sweden using data from a large-scale longitudinal cross-sectional database.

Categorization flexibility and unconventional choices: is life an adventure?

2020 ◽  
Vol 54 (8) ◽  
pp. 1963-1986
Author(s):  
Tilottama G. Chowdhury ◽  
Feisal Murshed
Keyword(s):  
Interactive Effect ◽  
Interactive Effects ◽  
Cognitive Capacity ◽  
Purchase Behavior ◽  
Consumer Decision Making ◽  
Cross Sectional ◽  
Content Type ◽  
Cross Domain ◽  
Multiple Domains

Purpose This paper proposes that categorization flexibility, operationalized as the cognitive capacity that cross-categorizes products in multiple situational categories across multiple domains, might favorably influence a consumer’s evaluation of unconventional options. Design/methodology/approach Experimental research design is used to test the theory. An exploratory study first establishes the effect of categorization flexibility in a non-food domain. Study 1 documents the moderating role of decision domain, showing that the effect works only under low- (vs high-) consequence domain. Studies 2A and 2B further refine the notion by showing that individuals can be primed in a relatively higher categorization flexibility frame of mind. Study 3 demonstrates the interactive effect of categorization flexibility and adventure priming in a high-consequence domain. Study 4 integrates the interactive effects of decisions with low- vs high-consequence, adventure priming and categorization flexibility within a single decision domain of high consequence. Findings Consumers with higher- (vs lower-) categorization flexibility tend to opt for unconventional choices when the decision domain entails low consequences, whereas such a result does not hold under decision domain of high consequences. The categorization flexibility effects in case of low-consequence decision domain holds true even when consumers are primed to be categorization flexible. Furthermore, with additional adventure priming, consumers show an increased preference for unconventional options even under a decision domain with high consequence. Research limitations/implications This study could not examine real purchase behavior as results are based on cross-sectional, behavioral intention data. In addition, it did not examine the underlying reason for presence of cross-domain categorization flexibility index. Practical implications The results suggest that stimuli may be tailored to consumers in ways that increase the salience and the perceived attractiveness of unconventional choices. Further, data reinforce the notion of cross-categorical interrelations among different domains, which could be leveraged by marketers. Originality/value This study represents the first documentation of the potential ways by which unconventional product choice might be a function of individuals’ categorization flexibility level across different types of decision domains. The findings yield implications that are novel to both categorization and consumer decision-making literature.

Engaging leadership in the job demands-resources model

2015 ◽  
Vol 20 (5) ◽  
pp. 446-463 ◽  
Author(s):  
Wilmar B. Schaufeli
Keyword(s):  
Structural Equation ◽  
Work Performance ◽  
Online Survey ◽  
Job Demands ◽  
Well Being ◽  
Organizational Outcomes ◽  
Job Resources ◽  
Equation Modeling ◽  
Cross Sectional ◽  
Content Type

Purpose – The purpose of this paper is to integrate leadership into the job demands-resources (JD-R) model. Based on self-determination theory, it was argued that engaging leaders who inspire, strengthen, and connect their followers would reduce employee’s levels of burnout and increase their levels of work engagement. Design/methodology/approach – An online survey was conducted among a representative sample of the Dutch workforce (n=1,213) and the research model was tested using structural equation modeling. Findings – It appeared that leadership only had an indirect effect on burnout and engagement – via job demands and job resources – but not a direct effect. Moreover, leadership also had a direct relationship with organizational outcomes such as employability, performance, and commitment. Research limitations/implications – The study used a cross-sectional design and all variables were based on self-reports. Hence, results should be replicated in a longitudinal study and using more objective measures (e.g. for work performance). Practical implications – Since engaged leaders, who inspire, strengthen, and connect their followers, provide a work context in which employees thrive, organizations are well advised to promote engaging leadership. Social implications – Leadership seems to be a crucial factor which has an indirect impact – via job demands and job resources – on employee well-being. Originality/value – The study demonstrates that engaging leadership can be integrated into the JD-R framework.

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