Although thermoplastic beams with and without FRP reinforcements are currently being used primarily in marine and waterfront applications, they hold an immense potential for use in civil engineering structures such as bridges and buildings. Herein is presented a summary of an experimental and theoretical study of the flexural behavior of a commercially available type of thermoplastic beam known as Seatimber. Test and anlaytical results are presented for simply-supported beams subjected to a gradually increasing midspan concentrated load. Theoretical predictions are based on a nonlinear moment-curvature analysis coupled with a central finite-difference scheme. Experimental stress-strain curves are generated in both tension and compression for the thermoplastic and FRP rebars for use in a detailed analysis of the cross section. For this purpose, the cross section is divided into a large number of elemental areas to account for the radially varying nonlinear stress-strain material curves, as part of an iterative tangent stiffness algorithm leading to a moment-curvature relation. The theoretical and experimental results are in good agreement. Next, simplified criteria for a Load and Resistance Factor Design (LRFD) approach is outlined and its use demonstrated through analysis and design examples.
展开▼
