M.M Attar - Member of academic staff of Islamic Azad University, Hamadan Branch
M Haghpanahi - Associate Professor, Iran University of Science & Technology, Tehran, Iran

In this paper effects of mechanical and physical properties of polymer matrices of hybrid unidirectional fiber-reinforced composites with broken fibers are investigated, numerically and analytically. It is assumed that all fibers lie in one direction while loaded by a force po at infinity. The matrix and the fibers are considered homogeneous, isotropic and linearly elastic. To study effects of hybridization two types fiber arrangements are presented. The analytical solution is obtained using shear-lag and improved shear-lag theory. The analytical results based on two models, were compared to those of finite element values. Comparison of the predicted shear stresses and average normal stresses to finite element analysis demonstrates that improved shear-lag model can be used to rapidly estimate the average normal stress distribution in the various constituents, although the interfacial shear stresses are less accurate.

Hybrid composite materials; laminate; finite element method; stress concentration;analytical solutions