In this paper the mechanical properties of the cracked structures are investigated using the equivalent medium theory. Based on the definition of the surface damaged layer, the two-material composite beam is used to model the cracked beam. The differential equation of the deflection curve of the cracked beam is deduced. The effects of the damaged layer on the bending deformation are studied. The relation among the beam deflection, thickness of the influence of the damaged layer and the equivalent elastic modulus of the damaged part is obtained. In addition, damaged reveal that the deflection damage layer is Bess of d layer increases larger than 3% the beam are so the the layer thickness ＆ modulus on the beam stiffness is also evaluated. The numerical results of the beam will increase and the stiffness of the beam will decrease as the thickness of the or the elastic modulus of the damaged layer decreases. When the thickness of the damaged of the thickness of the beam, the influence of the damaged layer on the deflection and stiff- obviously that will affect the accuracy during the manufacturing process significantly.
Mechanical Science and Technology
deflection （ structures ）