Fiber reinforced plastic (FRP) beam sections, produced by the pultrusion process for load-bearing structural engineering applications, are manufactured by a number of U.S. companies. For design purposes both stiffness and strength properties of these structural members are required. The shear stiffness of pultruded FRP beams is considered in this paper. A new material/structural stiffness property, called the beam section shear modulus, is proposed. Using the beam section shear modulus, a procedure is presented to account for the effects of shear deformation on the response of FRP beams. Results of an experimental program conducted to obtain the section shear modulus for a variety of commercially produced FRP beams are reported. Values of the section flexural modulus for FRP beams are also given. The analysis of a rigid portal frame structure is presented to demonstrate the influence of the beam section stiffness properties on frame deflections and forces.
Abstract