COMPRESSION RESPONSE OF FIBER-REINFORCED COMPOSITE TUBES

As fiber reinforced composite materials become more attractive for use in many structural applications, the need to understand the mechanica l response of these materials becomes more urgent. This paper describe the results of the compression response of E-glass/epoxy composite la minated tubes under an axial compression pressure using a finite eleme nt method and experimental test. Normal stresses as well as the interl aminar normal and the interlaminar shear stresses are calculated using the finite element method. The effect of the thickness of the layers, the winding angle, and the endcaps on the strength of the composite t ubes are investigated. The Tsai-Wu and the maximum stress failure crit eria are used to discuss the failure response of the tubes. Although t he samples which have only layers with fiber orientation +/-10 degrees should give the highest compressive strength according to the classic al laminate theory, the experimental results do not agree with the lam ination theory in this point and delamination of the +/-10 degrees lay ers occurs and the maximum strength drops. The results also indicate t hat the interaction between the stresses can lead to failure processes even the stresses are still under the maximum allowable values.