The interlaminar stresses are analyzed by combining the first shear theory with the layerwise theory method. And the plate subjected to a uniform axial strain is studied by the simplified displacement field. Using the...The interlaminar stresses are analyzed by combining the first shear theory with the layerwise theory method. And the plate subjected to a uniform axial strain is studied by the simplified displacement field. Using the simplified displacement field, the equations of finite element method is developed by the principle of virtual work. And the amount of calculation is reduced by using the linear element. Then, some numerical examples are given to verify the accuracy of the method and analyze the distribution of interlaminar stresses along y-axis and z-axis. The shapes of the stresses’ curves in the vicinity of the free edge are very different from the interior area. Moreover, the influence of the ply angle on the interlaminar stresses is analyzed for the plate [θ/-θ]s. It can be found that the shapes of the stresses along z-axis are similar when the angle is different, while the values of the interlaminar stresses are changed apparently with the ply angle.展开更多
In the symplectic space composed of the original variables,displacements,and their dual variables,stresses,the symplectic solution for the composite laminates based on the Pipes-Pagano model is established in this pap...In the symplectic space composed of the original variables,displacements,and their dual variables,stresses,the symplectic solution for the composite laminates based on the Pipes-Pagano model is established in this paper.In contrast to the traditional technique using only one kind of variables,the symplectic dual variables include displacement components as well as stress components.Therefore,the compatibility conditions of displacement and stress at interfaces can be formulated simultaneously.After being introduced into the symplectic dual system,the uniform schemes,such as the separation of variables and symplectic eigenfunction expansion method,can be implemented conveniently to analyze composite laminate problems.An analytical solution for the free edge effect of composite laminates is obtained,showing the effectiveness of the symplectic dual method in analyzing composite laminates.展开更多
文摘The interlaminar stresses are analyzed by combining the first shear theory with the layerwise theory method. And the plate subjected to a uniform axial strain is studied by the simplified displacement field. Using the simplified displacement field, the equations of finite element method is developed by the principle of virtual work. And the amount of calculation is reduced by using the linear element. Then, some numerical examples are given to verify the accuracy of the method and analyze the distribution of interlaminar stresses along y-axis and z-axis. The shapes of the stresses’ curves in the vicinity of the free edge are very different from the interior area. Moreover, the influence of the ply angle on the interlaminar stresses is analyzed for the plate [θ/-θ]s. It can be found that the shapes of the stresses along z-axis are similar when the angle is different, while the values of the interlaminar stresses are changed apparently with the ply angle.
基金supported by the National Basic Research Program of China (No. 2010CB832704)the National Natural Science Foundation of China (No. 10772039)
文摘In the symplectic space composed of the original variables,displacements,and their dual variables,stresses,the symplectic solution for the composite laminates based on the Pipes-Pagano model is established in this paper.In contrast to the traditional technique using only one kind of variables,the symplectic dual variables include displacement components as well as stress components.Therefore,the compatibility conditions of displacement and stress at interfaces can be formulated simultaneously.After being introduced into the symplectic dual system,the uniform schemes,such as the separation of variables and symplectic eigenfunction expansion method,can be implemented conveniently to analyze composite laminate problems.An analytical solution for the free edge effect of composite laminates is obtained,showing the effectiveness of the symplectic dual method in analyzing composite laminates.
