Simplification of Failure-Based Composite Design Using General Isotropic Linear FE Softwares for Classical Lamination Shell Theory

摘要

The design of plate and shell structures using special finite element analysis have a certain quite long procedures, especially for multilayered composite cases. Their material complexity lead to expensive analysis time due to degree of freedom caused by an arduous calculation related angle plies configuration, stack sequences, local and global propertiesand discontinuities of stress distribution both normal and interlaminar shear stresses. Composite analysis softwares are very expensive and difficult to operate due their complicated input they ask. Engineers need something practical but accurate enough for design purpose, so the failure limits should be predicted and known well. For design purpose or preliminary design, a very standard displacement based finite element software actually can be used because the stresses is quite independent from material, a well known principal from ordinary structures book. Unlike the displacement and the strain that they have a sharp relationship with the material. In this study, the use of general homogeneous linear isotropic software to solve complex structures, such as multilayered composite plate and shells is introduced. Here, researchers use the internal forces and or stresses found from an ordinary simple software and modified them to take secondary behavior into account and enrich their output into an accurate enough failure stresses for design purpose assessments. Hence, the well known {d} displacement and {ε} strain results are bypassed. After finds the global internal forces, instead of this neglecting, Tsai-Hill criterion will be judged to ensure the safety of each lamina. This proposed design method will be an accurate-efficient method in multilayered composites design.