The Experts below are selected from a list of 27 Experts worldwide ranked by ideXlab platform

V G Mokos - One of the best experts on this subject based on the ideXlab platform.

  • 3 d beam element of composite cross section including warping and shear deformation effects
    Computers & Structures, 2007
    Co-Authors: E J Sapountzakis, V G Mokos
    Abstract:

    In this paper a boundary element method is developed for the construction of the 14x14 stiffness matrix and the Nodal Load Vector of a member of arbitrary homogeneous or composite cross section taking into account both warping and shear deformation effects. The composite member consists of materials in contact each of which can surround a finite number of inclusions. To account for shear deformations, the concept of shear deformation coefficients is used. In this investigation the definition of these factors is accomplished using a strain energy approach. Seven boundary value problems are formulated and solved employing a pure BEM approach, that is only boundary discretization is used. The evaluation of the shear deformation coefficients is accomplished from stress functions using only boundary integration. Numerical results are presented to illustrate the method and demonstrate its efficiency and accuracy. The influence of the warping effect especially in composite members of open form cross section is analyzed through examples demonstrating the importance of the inclusion of the warping degrees of freedom in the analysis of a space frame. Moreover, the discrepancy of both the deflections and the internal forces of a member of a spatial structure arising from the ignorance of the shear deformation effect necessitates the inclusion of this additional effect, especially in thick walled cross section members.

E J Sapountzakis - One of the best experts on this subject based on the ideXlab platform.

  • 3 d beam element of composite cross section including warping and shear deformation effects
    Computers & Structures, 2007
    Co-Authors: E J Sapountzakis, V G Mokos
    Abstract:

    In this paper a boundary element method is developed for the construction of the 14x14 stiffness matrix and the Nodal Load Vector of a member of arbitrary homogeneous or composite cross section taking into account both warping and shear deformation effects. The composite member consists of materials in contact each of which can surround a finite number of inclusions. To account for shear deformations, the concept of shear deformation coefficients is used. In this investigation the definition of these factors is accomplished using a strain energy approach. Seven boundary value problems are formulated and solved employing a pure BEM approach, that is only boundary discretization is used. The evaluation of the shear deformation coefficients is accomplished from stress functions using only boundary integration. Numerical results are presented to illustrate the method and demonstrate its efficiency and accuracy. The influence of the warping effect especially in composite members of open form cross section is analyzed through examples demonstrating the importance of the inclusion of the warping degrees of freedom in the analysis of a space frame. Moreover, the discrepancy of both the deflections and the internal forces of a member of a spatial structure arising from the ignorance of the shear deformation effect necessitates the inclusion of this additional effect, especially in thick walled cross section members.

Mokos V.g. - One of the best experts on this subject based on the ideXlab platform.

  • Dynamic analysis of 3-D beam elements including warping and shear deformation effects
    Elsevier Ltd., 2006
    Co-Authors: Sapountzakis E.j., Mokos V.g.
    Abstract:

    AbstractIn this paper the dynamic analysis of 3-D beam elements restrained at their edges by the most general linear torsional, transverse or longitudinal boundary conditions and subjected in arbitrarily distributed dynamic twisting, bending, transverse or longitudinal Loading is presented. For the solution of the problem at hand, a boundary element method is developed for the construction of the 14×14 stiffness matrix and the corresponding Nodal Load Vector of a member of an arbitrarily shaped simply or multiply connected cross section, taking into account both warping and shear deformation effects, which together with the respective mass and damping matrices lead to the formulation of the equation of motion. To account for shear deformations, the concept of shear deformation coefficients is used, defining these factors using a strain energy approach. Eight boundary value problems with respect to the variable along the bar angle of twist, to the primary warping function, to a fictitious function, to the beam transverse and longitudinal displacements and to two stress functions are formulated and solved employing a pure BEM approach that is only boundary discretization is used. Both free and forced transverse, longitudinal or torsional vibrations are considered, taking also into account effects of transverse, longitudinal, rotatory, torsional and warping inertia and damping resistance. Numerical examples are presented to illustrate the method and demonstrate its efficiency and accuracy. The influence of the warping effect especially in members of open form cross section is analyzed through examples demonstrating the importance of the inclusion of the warping degrees of freedom in the dynamic analysis of a space frame. Moreover, the discrepancy in the dynamic analysis of a member of a spatial structure arising from the ignorance of the shear deformation effect necessitates the inclusion of this additional effect, especially in thick walled cross section members

Sapountzakis E.j. - One of the best experts on this subject based on the ideXlab platform.

  • Dynamic analysis of 3-D beam elements including warping and shear deformation effects
    Elsevier Ltd., 2006
    Co-Authors: Sapountzakis E.j., Mokos V.g.
    Abstract:

    AbstractIn this paper the dynamic analysis of 3-D beam elements restrained at their edges by the most general linear torsional, transverse or longitudinal boundary conditions and subjected in arbitrarily distributed dynamic twisting, bending, transverse or longitudinal Loading is presented. For the solution of the problem at hand, a boundary element method is developed for the construction of the 14×14 stiffness matrix and the corresponding Nodal Load Vector of a member of an arbitrarily shaped simply or multiply connected cross section, taking into account both warping and shear deformation effects, which together with the respective mass and damping matrices lead to the formulation of the equation of motion. To account for shear deformations, the concept of shear deformation coefficients is used, defining these factors using a strain energy approach. Eight boundary value problems with respect to the variable along the bar angle of twist, to the primary warping function, to a fictitious function, to the beam transverse and longitudinal displacements and to two stress functions are formulated and solved employing a pure BEM approach that is only boundary discretization is used. Both free and forced transverse, longitudinal or torsional vibrations are considered, taking also into account effects of transverse, longitudinal, rotatory, torsional and warping inertia and damping resistance. Numerical examples are presented to illustrate the method and demonstrate its efficiency and accuracy. The influence of the warping effect especially in members of open form cross section is analyzed through examples demonstrating the importance of the inclusion of the warping degrees of freedom in the dynamic analysis of a space frame. Moreover, the discrepancy in the dynamic analysis of a member of a spatial structure arising from the ignorance of the shear deformation effect necessitates the inclusion of this additional effect, especially in thick walled cross section members

Hai, Bui Thanh - One of the best experts on this subject based on the ideXlab platform.

  • Dynamic analysis of prestressed Bernoulli beams resting on two-parameter foundation under moving harmonic Load
    'Publishing House for Science and Technology Vietnam Academy of Science and Technology', 2006
    Co-Authors: Kien, Nguyen Dinh, Hai, Bui Thanh
    Abstract:

    This paper describes the dynamic analysis of prestressed Bernoulli beams resting on a two-parameter elastic foundation under a moving harmonic Load by the finite element method. Using the cubic Hermitian polynomials as interpolation functions for the deflection, the stiffness of the Bernoulli beam element augmented by that of the foundation support and prestress is formulated. The Nodal Load Vector is derived using the polynomials with the abscissa measured from the left-hand node of the current Loading element to the position of the moving Load. Using the formulated element, the dynamic response of the beams is computed with the aid of the direct integration Newmark method. The effects of the foundation support, prestress as well as excitation frequency, velocity and acceleration on the dynamic characteristics of the beams are investigated in detail and highlighted