Abstract

Tubular composite beams are of increasing interest due to their growing applications in the offshore and aerospace industries. Most analysis work done on tubular composite beams has been limited to pure bending, uniform axial loads or uniform torsion. These are also limited to the analysis of uniform section, uniform material and uniform thickness beams. In real applications, transverse shear loads are usually present and add complexity to the analyses. When a beam is under distributed or concentrated transverse loadings, regardless of the boundary conditions, the distributions of bending moments and internal transverse shear loads vary through the length of the beam. Analysis of such beams is very complicated. In this research, a systematic approach is presented to evaluate shear stress distribution across the cross section of thin walled tubular beams made of non homogeneous sections. Variation of shear stress through the thickness is ignored. Exact equations for the analysis of shear stresses in thin wall composite beams are derived in local coordinate systems. The results are projected in global coordinate system to facilitate evaluation and comparison of shear stress distribution in different beams. The method is applied to analyze beams with T, Triangular, Hexagonal, Octagonal and Decagonal sections. The pattern behaviour and shear stress variation in these beams is studied to predict the maximum shear stress in beams with circular cross section that has the same radius as the circumscribed circle of multi-gonal beams