Negative Shear Lag Effect in Continuous Double T Beam by FEM

Abstract

This paper presents the use of a finite element method (FEM) to analyze the negative shear lag effect on prestressed continuous double T beam. However, the numerical method can be applied to i) any cross-section, ii). the most common types of supports, such as fixed, pinned, roller, iii) and any applied load, concentrated, or distributed passed through the shear center of the crosssection. The characteristics of the cross-section are firstly derived from 2D FEM, which uses a 9-node isoparametric element. Then, a 1D FEM, which uses a linear isoparametric element, is developed to compute the deflection, rotation angle, bending warping parameter, and stress resultants. Finally, the stress field is obtained from the local analysis on the 2D-cross section. A MATLAB program is executed to validate the numerical method.