tailieunhanh - Effects of shear deformation on large deflection behavior of elastic frames

In this paper, the effects of shear deformation on the large deflection behavior of elastic frames is investigated by the finite element method. A two-node nonlinear beam element with the shear deformation is formulated and employed to analyze some frame structures. | Vietnam Journal of Mechanics, VAST, Vol. 26 , 2004, No. 3 (167 - 181) EFFECTS OF SHEAR DEFORMATION ON LARGE DEFLECTION BEHAVIOR OF ELASTIC FRAMES NGUYEN DINH KIEN Institute of Mechanics ABSTRACT. In this paper, the effects of shear deformation on the large deflection behavior of elastic frames is investigated by the finite element method . A two-node nonlinear beam element wit h the shear deformation is formulated and employed to analyze some frame structures. The element based on the energy method is developed in the context of the corotational approach. A bracketing procedure u ed the lowest eigenvalue of structural tangent · stiffness matrix as indicating parameter is adopted to compute the critical loads. An incremental/ iterative procedure with the arc-length control technique is employed to trace the equilibrium paths. The numerical results show that the shear deformation plays an important role in the critical load and the large deflection behavior of the frames constructed from the components having low slenderness. A detail investigation is carried out to highlight the influence of slenderness on the behavior of the frames under large deflection. 1 Introduction With the increment of using high performance material in practice, the structures can undergo la rge deformation before failure , and this phenomenon accelerates the importance of nonlinear analysis in the field of structural mechanics . It is well known that the finite element method is an effective tool in solving nonlinear problems of structures, and some commercial finite element programs, including MARC , SAP , ANSYS, ABAQUS and ADINA , have incorporated the nonlinear elements to make them possible for nonlinear analysis [1] In the previous works [2, 3], t he author and his co-worker have formulated some nonlinear beam elements for large deflection analysis of elastic frame structures. The beam elements developed in the work are based on the Euler-Bernoulli beam theory, in which a plane .