Mixed FEM of B-Spline Wavelet on Interval for Beam Structures

A mixed finite element method(FEM) of B-spline wavelet on the interval(BSWI) for beam structures was proposed based on the generalized variational principle of beam structure and interpolation of BSWI,and general equations for solving static problem,vibration modal problem and stability problem of long beams and elastic foundation beams were presented.The deflection and moment wavelet parameters for common boundary conditions of beams were obtained from numerical features of interval boundary of BSWI functions.The proposed method directly gets deflection and moment of beam structures at the same time,and overcomes the shortcoming of low accuracy in beam moment calculation of displacement FEM.Numerical results show that the proposed method increases beam moment calculation accuracy by 10.9% compared with displacement FEM of BSWI,demonstrating its feasibility and high accuracy in applications to beam structure problems.