Mechanical properties analysis of bilayer Euler-Bernoulli beams based on elasticity theory

Document Type: Original Article


This paper analyzes the effects of structures and loads on the static bending and free vibration problems of bilayer beam. Based on static mechanical equilibrium and energy equilibrium, the static and dynamic governing equations of bilayer beam are established. Two boundary value problems of the cantilever beam and simply supported beam are solved and static bending and free vibration for two kinds of boundary conditions are assessed. It is found that the value of the thickness ratio and length thick ratio have a significant effect on the static and dynamic responses of the beams, and the structure factors have their own critical value. When the value of the relative thickness lower than its critical value or the length thickness ratio is greater than its critical value, the static and dynamic responses of the beams is increased obviously. In addition, the static and dynamic responses of a cantilever beam is much larger than that of a simply supported beam, under the same structure, load and material. The results reveal that it exists critical structure values in bilayer beams, the values have noticeable influence on the mechanical properties of bilayer beams. Therefore, investigators should predict the critical structures accurately, when they design the bilayer beam. And the results also verified that simply supported beams are more stable than cantilever beams. This article can provide a reference for engineers to design bilayer beam.