Elastic Distortional Buckling Analysis of I-Steel Concrete Composite Beam Considering Shear Deformation

2016 ◽  
Vol 16 (08) ◽  
pp. 1550045 ◽  
Author(s):  
Wang-Bao Zhou ◽  
Li-Zhong Jiang ◽  
Shu-Jin Li ◽  
Fan Kong
Keyword(s):  
Shear Deformation ◽  
Composite Beam ◽  
Coupling Effect ◽  
Bottom Flange ◽  
Distortional Buckling ◽  
Related Factors ◽  
Factors Affecting ◽  
Buckling Stress ◽  
Negative Moment ◽  
Applied Forces

Elastic distortional buckling is one of the essential buckling modes of the I-steel concrete composite beam (ISCCB); such buckling often occurs under the gradient of negative moment. The key factors affecting the kind of buckling are the “torsional” and “lateral” restraint stiffnesses of the bottom flange of the beam. This paper investigates the equivalent lateral and torsional restraint stiffnesses of the bottom flange of the ISCCB under the gradient of negative moment. The relations for estimating the lateral and torsional restraint stiffnesses are used to determine the critical distortional buckling stress and associated buckling moment of the beam under the gradient of negative moment. A new method is proposed for assessing the buckling of the elastic-foundation beam, by which the related factors are considered: (1) The coupling effect between the applied forces and lateral/torsional restraint stiffness of the bottom flange of the beam, (2) the effect of gradient of a moment and (3) the effect of shear deformation of the web. The proposed method has been compared with those available by using the data of 15 cases under different loading conditions; the results show that the present method is much more accurate and reliable than the existing ones. The method as proposed herein is recommended for further research in relation to the buckling of the ISCCB.

scholarly journals Distortional Buckling Analysis of Steel-Concrete Composite Girders in Negative Moment Area

2014 ◽  
Vol 2014 ◽  
pp. 1-10 ◽  
Author(s):  
Zhou Wangbao ◽  
Jiang Lizhong ◽  
Kang Juntao ◽  
Bao Minxi
Keyword(s):  
Coupling Effect ◽  
Bending Moment ◽  
Bottom Flange ◽  
Distortional Buckling ◽  
Box Girders ◽  
Composite Girder ◽  
Axial Forces ◽  
Negative Moment ◽  
Applied Forces ◽  
Composite Girders

Distortional buckling is one of the most important buckling modes of the steel-concrete composite girder under negative moment. In this study, the equivalent lateral and torsional restraints of the bottom flange of a steel-concrete composite girder under negative moments due to variable axial forces are thoroughly investigated. The results show that there is a coupling effect between the applied forces and the lateral and torsional restraint of the bottom flange. Based on the calculation formula of lateral and torsional restraints, the critical buckling stress of I-steel-concrete composite girders and steel-concrete composite box girders under variable axial force is obtained. The critical bending moment of the steel-concrete composite girders can be further calculated. Compared to the traditional calculation methods of elastic foundation beam, the paper introduces an improved method, which considers coupling effect of the external loads and the foundation spring constraints of the bottom flange. Fifteen examples of the steel-concrete composite girders in different conditions are calculated. The calculation results show a good match between the hand calculation and the ANSYS finite element method, which validated that the analytic calculation method proposed in this paper is practical.

scholarly journals Lateral distortional buckling of cellular composite-beams

2018 ◽  
Vol 11 (2) ◽  
pp. 331-356 ◽  
Author(s):  
A. D. PIASSI ◽  
J. V. DIAS ◽  
A. F. G. CALENZANI ◽  
F. C. C. MENANDRO
Keyword(s):  
Flexural Rigidity ◽  
Lateral Displacement ◽  
Limit State ◽  
Composite Beams ◽  
Bottom Flange ◽  
Distortional Buckling ◽  
Critical Moment ◽  
Negative Moment ◽  
Resistant Moment ◽  
Negative Bending

Abstract In the region of negative bending moments of continuous and semi-continuous steel and concrete composite beams, the inferior portion of the steel section is subjected to compression while the top flange is restricted by the slab, which may cause a global instability limit state know as lateral distortional buckling (LDB) characterized by a lateral displacement and rotation of the bottom flange with a distortion of the section’s web when it doesn’t have enough flexural rigidity. The ABNT NBR 8800:2008 provides an approximate procedure for the verification of this limit state, in which the resistant moment to LDB is obtained from the elastic critical moment in the negative moment region. One of the essential parameters for the evaluation of the critical moment is the composite beam’s rotational rigidity. This procedure is restricted only to to steel and concrete composite beams with sections that have plane webs. In this paper, an equation for the calculation of the rotational rigidity of cellular sections was developed in order to determine the LDB elastic critical moment. The formulation was verified by numerical analyses performed in ANSYS and its efficiency was confirmed. Finally, the procedure described in ABNT NBR 8800:2008 for the calculation of the critical LDB moment was expanded to composite beams with cellular sections in a numerical example with the appropriate modifications in geometric properties and rotational rigidity.

scholarly journals Lateral Buckling Analysis of the Steel-Concrete Composite Beams in Negative Moment Region

2015 ◽  
Vol 2015 ◽  
pp. 1-8
Author(s):  
Fengqi Guo ◽  
Shun Zhou ◽  
Lizhong Jiang
Keyword(s):  
Composite Beam ◽  
Engineering Application ◽  
Bottom Plate ◽  
Variation Principle ◽  
Steel Beam ◽  
Key Factors ◽  
Distortional Buckling ◽  
Buckling Behavior ◽  
Negative Moment ◽  
Analytical Expressions

Distortional buckling is one of the important buckling models of steel-concrete composite beam in negative moment region. Rotation restraining rigidity and lateral restraining rigidity which steel beam web to bottom plate of steel-concrete composite are the key factors to influence the distortional buckling behavior. A comprehensive and intensive study on rotation restraining rigidity and lateral restraining rigidity which steel beam web to bottom plate of I-shaped steel-concrete composite beam in negative moment region is conducted in this paper. Energy variation principle is adopted to deduce the analytical expressions to calculate the rotation restraining rigidity and lateral restraining rigidity. Combined with the buckling theory of axial compression thin-walled bars in elastic medium, the buckling moment is obtained. Theoretical analysis shows that the rotation restraining rigidity and lateral restraining rigidity of steel beam web appear to have a linear relationship with the external loads and could also be negative. Compared with other methods, the results calculated by the proposed expressions agree well with the numerical results by ANSYS. The proposed expressions are more concise and suitable than the existing formulas for the engineering application.

Consumer Online Buying Decisions: A Critical Appraisal of Literature

2017 ◽  
Vol 10 (1) ◽  
Author(s):  
Amit Kishore Sinha ◽  
Gyanendra B. S. Johri ◽  
Shanti Rai
Keyword(s):  
Research Paper ◽  
Business Environment ◽  
Buying Behavior ◽  
Related Factors ◽  
Factors Affecting ◽  
Goods And Services ◽  
Online Stores ◽  
Online Buying ◽  
Indian Cities ◽  
Buying Decisions

Since last two decades buying of goods and services from online stores using Internet started off. But players of this industry could reach to the general public residing in second and third category Indian cities in recent past only. Now companies are eagerly interested in understanding the factors affecting Indian consumers so that their needs and wants can be understood and served profitably. This research paper is an attempt to critically evaluate those factors which affect consumer buying behavior in Indian Internet based business environment. For the purpose of coverage of topic researcher has classified the literature under three categories which are Literature related to vendor related factors, Literature related to consumer related factors and Literature related to other factors. Vendor related factors include those factors which are primarily controlled by the companies that are engaged in selling their goods and services on internet along with their intermediaries through which such sales take place. Consumer related factors have been bifurcated under two heading that are consumer demographic factors and consumer psychographic factors. Besides this there are several other factors which may affect consumer’s buying decisions and they are classified as other factors. This research paper also tries to identify the gaps (if any) in the available literature of the factors affecting consumer online buying decisions.

scholarly journals Investigating the status of marital burnout and related factors in married women referred to health centers

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Mahbobeh Nejatian ◽  
Ali Alami ◽  
Vahideh Momeniyan ◽  
Ali Delshad Noghabi ◽  
Alireza Jafari
Keyword(s):  
Marital Satisfaction ◽  
Significant Relationship ◽  
Married Couples ◽  
Married Women ◽  
Health Centers ◽  
Related Factors ◽  
Factors Affecting ◽  
The Status ◽  
Multistage Sampling ◽  
Emotional Burnout

Abstract Background Marital burnout is an important issue in marriage and many factors play an important role in this phenomenon. The aim of this study was to determine the status of marital burnout and the factors affecting married women who were referred to health centers because of it. Methods In this study, 936 women were selected by multistage sampling and data collection was performed using questionnaires of demographic and couple burnout. Data analysis was performed using SPSS software version 24. Results The mean (± SD) of marital burnout, in this study, was 55.46 (± 18.03) (out of 147 score). There was a significant relationship between the level of women's education with total marital burnout, and the subscales of somatic and emotional burnout (P < 0.05). A significant relationship was also observed between mandatory marriage and total marital burnout, as well as subscales of somatic, emotional, and psychological burnout (P < 0.05). A significant relationship was detected and observed between women's participation in training courses of communication skills and total marital burnout, inclusive of the subscales regarding psychological burnout (P < 0.05). The results of linear regression showed a significant relationship between mandatory in marriage, marital satisfaction, marriage duration, and husband's level of education with women's marital burnout. The variables were finally able to predict 12% of marital burnout variance. It should be noted that marital satisfaction had a higher effect on predicting marital burnout (P < 0.001). Conclusions Marital satisfaction was one of the effective factors in predicting marital burnout, so it can be concluded that it is necessary to pay more attention to this issue. Educational programs and examining the factors that enhance marital satisfaction are needed to prevent and reduce marital burnout in married couples.

scholarly journals What Affects Chinese Residents’ Perceptions of Climate Change?

2018 ◽  
Vol 10 (12) ◽  
pp. 4712 ◽  
Author(s):  
Jinjia Wu ◽  
Jiansheng Qu ◽  
Hengji Li ◽  
Li Xu ◽  
Hongfen Zhang ◽  
...  
Keyword(s):  
Climate Change ◽  
Public Awareness ◽  
Public Understanding ◽  
Related Factors ◽  
Climate Change Risk ◽  
Climate Governance ◽  
Factors Affecting ◽  
National Education ◽  
The Public ◽  
Mitigation And Adaptation

The theme of global sustainable development has changed from environmental management to climate governance, and relevant policies on climate governance urgently need to be implemented by the public. The public understanding of climate change has become the prerequisite and basis for implementing various climate change policies. In order to explore the affected factors of climate change perception among Chinese residents, this study was conducted across 31 provinces and regions of China through field household surveys and interviews. Combined with the residents’ perception of climate change with the possible affected factors, the related factors affecting Chinese residents’ perception of climate change were explored. The results show that the perceptive level of climate change of Chinese residents is related to the education level and the household size of residents. Improving public awareness of climate change risk in the context of climate change through multiple channels will also help to improve residents’ awareness of climate change. On the premise of improving the level of national education, improving education on climate change in school education and raising awareness of climate change risk among dependents will help to improve the level of Chinese residents’ awareness of climate change, which could be instrumental in promoting public participation in climate change mitigation and adaptation actions.

Unfilled Training Positions in Germany – Regional and Establishment-Specific Determinants

2019 ◽  
Vol 239 (4) ◽  
pp. 661-701 ◽  
Author(s):  
Sandra Dummert ◽  
Ute Leber ◽  
Barbara Schwengler
Keyword(s):  
Related Factors ◽  
Factors Affecting ◽  
External Conditions ◽  
Western Germany ◽  
Enterprise Level ◽  
Specific Factors ◽  
Regional Factors ◽  
The One ◽  
Training Position ◽  
Quantitative Importance

AbstractThe current situation in the German apprenticeship market is characterized by two contradictory developments. On the one hand, establishments are experiencing increasing problems filling the training positions they offer, and the number of vacant training positions is climbing. On the other hand, the transition into training is still difficult for many young people, and the number of unsuccessful vocational training applicants is rising. Hence, matching supply with demand is becoming increasingly difficult in the German job market for training positions. Using the Linked Employer-Employee dataset (LIAB) from the Institute for Employment Research (IAB), our paper provides a closer examination of the phenomenon of unfilled training positions. It presents an overview of the evolution of vacant training positions in eastern and western Germany and attempts to explain the number of vacancies by investigating the factors responsible for the establishments’ inability to fill their training positions. We assume that training position vacancies are due not only to internal company reasons such as firm size or the wage offer for apprentices but also to external conditions such as general regional factors. Therefore, our analysis also considers the situation on the demand side of the labor market within a region. The results of our multilevel mixed-effects estimations show that in addition to characteristics on the enterprise level, regional determinants also affect the share of vacant apprenticeships. With respect to establishment-related factors, mainly characteristics that describe the attractiveness of the firm prove to be important. With regard to regional-specific factors, we find that the availability of school leavers in a region in addition to the level of regional-sectoral competition impacts the recruiting success of establishments. Our analysis also shows that there are remarkable differences between eastern and western Germany concerning both the quantitative importance of unfilled training positions and the factors affecting them.

scholarly journals Understanding employee turnover in humanitarian organizations

2016 ◽  
Vol 48 (4) ◽  
pp. 208-214 ◽  
Author(s):  
Rameshwar Dubey ◽  
Angappa Gunasekaran ◽  
Nezih Altay ◽  
Stephen J Childe ◽  
Thanos Papadopoulos
Keyword(s):  
Employee Turnover ◽  
Factor Loading ◽  
Personal Factors ◽  
Related Factors ◽  
Content Type ◽  
Factors Affecting ◽  
Work Related ◽  
Humanitarian Organizations ◽  
Using Data ◽  
High Level

Purpose – At a time when the number and seriousness of disasters seems to be increasing, humanitarian organizations find that besides their challenging work they are faced with problems caused by a high level of turnover of staff. The paper aims to discuss these issues. Design/methodology/approach – Based on the 24 variables leading to employee turnover identified by Cotton and Tuttle (1986) the authors analyse the work-related, external and personal factors affecting employee turnover in humanitarian organizations, using a survey of members of the Indian National Institute of Disaster Management. Findings – Results indicated that the three factors are present. Of the external factors, only employment perception had a factor loading over 0.7; of the work-related factors, all were significant; of the personal factors, biographical information, marital status, number of dependants, aptitude and ability and intelligence had the highest loadings. It was also shown that behavioural intentions and net expectation were not significant. Originality/value – Only a few studies reported on employee turnover and its reasons are not well understood in the context of humanitarian organizations. To address this need, the aim of this paper is to explore the personal reasons impacting employee turnover in humanitarian organizations. In the study the authors have adopted 24 variables used in Cotton and Tuttle (1986) and classified into constructs to explain turnover, and further tested the model using data gathered from humanitarian organizations.

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