• Title/Summary/Keyword: Buckling

Search Result 2,826, Processing Time 0.086 seconds

Buckling Length Analysis for Compression Chord in Cold-Formed Steel Cantilever Truss

  • Konkong, Nirut;Aramraks, Trakool;Phuvoravan, Kitjapat
    • International journal of steel structures
    • /
    • v.17 no.2
    • /
    • pp.775-787
    • /
    • 2017
  • The lateral buckling of a cold-formed steel truss structure was investigated. Both an experimental test and finite element analysis presented a good correlation in the failure mechanism of specimens. The critical buckling load of the compression truss chord was analyzed using a South well plot and the analytical method. The transfer matrix method and the governing equation of an Euler column were used to analyze the critical buckling load of a multi-step, uniform chord member with lateral spring supports. Expressions for the buckling length factor presented according to AISI (2012) and the EN 1993-1-3 (2006) specification were compared by experimental testing and the analytical method. The buckling length factor of the experimental test and the analytical model confirmed that the buckling length of a compressed truss chord was less than the distance between the lateral bracing.

Geometrically Nonlinear Analysis of Eccentrically Stiffened Plates

  • Lee, Jae-Wook;Chung, Kie-Tae;Yang, Young-Tae
    • Selected Papers of The Society of Naval Architects of Korea
    • /
    • v.1 no.1
    • /
    • pp.91-100
    • /
    • 1993
  • A displacement-based finite element method Is presented for the geometrically nonlinear analysis of eccentrically stiffened plates. A nonlinear degenerated shell element and a nonlinear degenerated eccentric isoparametric beam (isobeam) element are formulated on the basis of Total Agrangian and Updated Lagrangian descriptions. In the formulation of the isobeam element, some additional local decrees of freedom are implementd to describe the stiffener's local plate buckling modes. Therefore this element can be effectively employed to model the eccentric stiffener with fewer D.O.F's than the case of a degenerated shell element. Some detailed buckling and nonlinear analyses of an eccentrically stiffened plate are performed to estimate the critical buckling loads and the post buckling behaviors including the local plate buckling of the stiffeners discretized with the degenerated shell elements and the isobeam elements. The critical buckling loads are found to be higher than the analytical plate buckling load but lower than Euler buckling load of the corresponding column, i.e, buckling strength requirements of the Classification Societies for the stiffened plates.

  • PDF

Inelastic buckling and post-buckling behavior of gusset plate connections

  • Hadianfard, Mohammad Ali;Khakzad, Ali Reza
    • Steel and Composite Structures
    • /
    • v.22 no.2
    • /
    • pp.411-427
    • /
    • 2016
  • In this study, by using finite element non-linear static analysis and comparing it with experimental models, the buckling and post-buckling behavior of bracing gusset plates has been investigated. The effects of such parameters as dimension and thickness of the gusset plate and the influence of position of the bracing member on the behavior of gusset plate have been examined. The results of the analyses clearly suggest that capacity, buckling and post-buckling behaviors of gusset plates depend on the position of the bracing splice plate with respect to the free bending line as well as on the size and thickness of the gusset plate. Also, with respect to numerical analysis results, some practical graphs for the calculation of buckling capacity of gusset plate connections are presented. For steel structures, the proposed method is apparently more accurate than available code procedures.

Large post-buckling behavior of Timoshenko beams under axial compression loads

  • Akbas, Seref D.
    • Structural Engineering and Mechanics
    • /
    • v.51 no.6
    • /
    • pp.955-971
    • /
    • 2014
  • Large post-buckling behavior of Timoshenko beams subjected to non-follower axial compression loads are studied in this paper by using the total Lagrangian Timoshenko beam element approximation. Two types of support conditions for the beams are considered. In the case of beams subjected to compression loads, load rise causes compressible forces end therefore buckling and post-buckling phenomena occurs. It is known that post-buckling problems are geometrically nonlinear problems. The considered highly non-linear problem is solved considering full geometric non-linearity by using incremental displacement-based finite element method in conjunction with Newton-Raphson iteration method. There is no restriction on the magnitudes of deflections and rotations in contradistinction to von-Karman strain displacement relations of the beam. The beams considered in numerical examples are made of lower-Carbon Steel. In the study, the relationships between deflections, rotational angles, critical buckling loads, post-buckling configuration, Cauchy stress of the beams and load rising are illustrated in detail in post-buckling case.

Exact buckling load of a restrained RC column

  • Krauberger, Nana;Saje, Miran;Planinc, Igor;Bratina, Sebastjan
    • Structural Engineering and Mechanics
    • /
    • v.27 no.3
    • /
    • pp.293-310
    • /
    • 2007
  • Theoretical foundation for the buckling load determination in reinforced concrete columns is described and analytical solutions for buckling loads of the Euler-type straight reinforced concrete columns given. The buckling analysis of the limited set of restrained reinforced concrete columns is also included, and some conclusions regarding effects of material non-linearity and restrain stiffnesses on the buckling loads and the buckling lengths are presented. It is shown that the material non-linearity has a substantial effect on the buckling load of the restrained reinforced concrete columns. By contrast, the steel/concrete area ratio and the layout of reinforcing bars are less important. The influence on the effective buckling length is small.

Buckling and post-buckling behaviors of 1/3 composite cylindrical shell with an opening

  • Ma, Yihao;Cheng, Xiaoquan;Wang, Zhaodi;Guo, Xin;Zhang, Jie;Xu, Yahong
    • Steel and Composite Structures
    • /
    • v.27 no.5
    • /
    • pp.555-566
    • /
    • 2018
  • A 1/3 composite cylindrical shell with a central rectangular opening was axially compressed experimentally, and its critical buckling load and displacement, and strains were measured. A finite element model (FEM) of the shell with Hashin failure criteria was established to analyze its buckling and post-buckling behaviors by nonlinear Newton-Raphson method. The geometric imperfection sensitivity and the effect of side supported conditions of the shell were investigated. It was found that the Newton-Raphson method can be used to analyze the buckling and post-buckling behaviors of the shell. The shell is not sensitive to initial geometric imperfection. And the support design of the shell by side stiffeners is a good way to obtain the critical buckling load and simplify the experimental fixture.

Thermal post-buckling analysis of a laminated composite beam

  • Akbas, Seref D.
    • Structural Engineering and Mechanics
    • /
    • v.67 no.4
    • /
    • pp.337-346
    • /
    • 2018
  • The purpose of this study is to investigate thermal post-buckling analysis of a laminated composite beam subjected under uniform temperature rising with temperature dependent physical properties. The beam is pinned at both ends and immovable ends. Under temperature rising, thermal buckling and post-buckling phenomena occurs with immovable ends of the beam. In the nonlinear kinematic model of the post-buckling problem, total Lagrangian approach is used in conjunction with the Timoshenko beam theory. Also, material properties of the laminated composite beam are temperature dependent: that is the coefficients of the governing equations are not constant. In the solution of the nonlinear problem, incremental displacement-based finite element method is used with Newton-Raphson iteration method. The effects of the fibber orientation angles, the stacking sequence of laminates and temperature rising on the post-buckling deflections, configurations and critical buckling temperatures of the composite laminated beam are illustrated and discussed in the numerical results. Also, the differences between temperature dependent and independent physical properties are investigated for post-buckling responses of laminated composite beams.

Post-buckling analysis of aorta artery under axial compression loads

  • Akbas, Seref Doguscan;Mercan, Kadir;Civalek, Omer
    • Advances in nano research
    • /
    • v.8 no.3
    • /
    • pp.255-264
    • /
    • 2020
  • Buckling and post-buckling cases are often occurred in aorta artery because it affected by higher pressure. Also, its stability has a vital importance to humans and animals. The loss of stability in arteries may lead to arterial tortuosity and kinking. In this paper, post-buckling analysis of aorta artery is investigated under axial compression loads on the basis of Euler-Bernoulli beam theory by using finite element method. It is known that post-buckling problems are geometrically nonlinear problems. In the geometrically nonlinear model, the Von Karman nonlinear kinematic relationship is employed. Two types of support conditions for the aorta artery are considered. The considered non-linear problem is solved by using incremental displacement-based finite element method in conjunction with Newton-Raphson iteration method. The aorta artery is modeled as a cylindrical tube with different average diameters. In the numerical results, the effects of the geometry parameters of aorta artery on the post-buckling case are investigated in detail. Nonlinear deflections and critical buckling loads are obtained and discussed on the post-buckling case.

Evaluation on the Buckling Length of Circular Hollow Steel with Ball Joints (볼접합부를 갖는 원형강관부재의 좌굴길이 평가)

  • Kang, Jong
    • Journal of the Korean Society of Industry Convergence
    • /
    • v.15 no.1
    • /
    • pp.5-11
    • /
    • 2012
  • The Buckling of the member under compressive stress is likely to occur, which is an important factor determining the strength of structures. The objective of this study was to evaluate the member buckling strength of a circular hollow steel with ball joints and to compare with design specifications for load resistance factor of our country. Furthermore, we would like to suggest basic data for evaluation of buckling length of a circular hollow steel with ball joints according to comparative analysis. These results were summarized as follows: Buckling stress according to the test results on buckling was 1.21 times greater than LSD specifications of our country estimated the entire length of circular hollow steel with ball joints as buckling length. In addition, it was 1.16 times greater than when estimating the length except the ball as buckling length and 1.14 times grater than when excluding the ball and sleeve. Therefore, when estimating buckling stress of circular hollow steel with ball joints, their buckling length may be measured by the length except ball and sleeve.

Design of the Stiffened Punch for Stamping of Lead Frame by Buckling Analysis (좌굴해석을 이용한 리드프레임 타발용 펀치의 보강설계)

  • Ko, Dae-Cheol;Lee, In-Soo;Ahn, Byung-Hwan;Kim, Byung-Min
    • Journal of the Korean Society for Precision Engineering
    • /
    • v.23 no.9
    • /
    • pp.68-75
    • /
    • 2006
  • The lead frame manufactured by stamping process plays an important role in connecting semiconductor to PCB board. As a result of the miniaturization of semiconductor, its corresponding lead frame punch has been narrow. In case of the punch with high slenderness ratio such as lead frame punch, the punch can be broken suddenly due to buckling. To prevent the fracture of lead frame punch, some manufacturers have experientially attached stiffeners to weak parts of punch. The purpose of this study, therefore, is to suggest the guideline far design of stiffened punch. The optimal position and the number of stiffeners to be attached to punch are investigated by elastic buckling analysis. The elastic buckling analysis consists of the eigenvalue buckling analysis and nonlinear buckling analysis. The critical buckling load of elastic buckling analysis is compared with that of buckling test. Finally, the guideline far attaching stiffeners is suggested through analysis of cross section of lead frame punch such as moment of inertia and eccentricity.