Failure criteria characterization of orthotropic beams under combined loads for stiffness and strength assessment

Resumo

Composites are no longer promising materials in the industry and have already become a reality in several applications. Their valuable properties such as high strength/weight ratio, durability, and corrosion resistance make them suitable for a vast range of applications. Looking for composites manufacturing, pultrusion is a technique that can produce closed and open-section profiles with a broad range of fiber orientation distribution throughout different areas of the cross-section. The process involves pulling reinforcement fibers through guides, immersing them in resin material, and placing them in a heated chamber to cure, all in a continuous process.
Various applications, including bridge construction, marine construction, transportation, and energy systems, have adopted these techniques. Typically, structural components can be simplified into beam-like components. These components can be exposed to different loading conditions in each application, usually in a combination of torsion, flexure, and traction, which have varying contributions to the total load. In this situation, creating new composite parts can be a difficult and time-consuming task because of the many variables involved. To address this issue, a previous investigation of this research focused on using the constant cross-section of extruded parts to analyse their free vibrational modes and frequencies. This analysis provided information on the stiffness distribution. However, this information alone does not provide all the necessary collection of data to draw robust conclusions. In this
sense, this work aims to investigate structures under combined loads in attempt to extract information about their static behavior. Along with this information a static analysis is also employed to generate failure curves, which are collections of points that characterizes the resistance of each cross section studied under different load contributions of bending and torsion. Thus, stiffness and resistance of different types of cross-sections, with multiple fiber angle distributions, can give valuable insights to the designer.