The effect of the radius to thickness ratio R/t on the interlaminar stresses around the hole in a [0/90]s composite laminate containing a circular hole and loaded in uniaxial tension was investigated. Three dimensional finite elements with a technique that is similar to substructuring were used for the analysis. The results show that as the ratio R/t increases, the magnitude of the tangential interlaminar shear stress on the interface between the crossed plies and near the hole edge increases. Also, as the ratio R/t in creases, the maximum of the interlaminar normal stress on the midplane near the hole increases and its position on the hole edge shifts towards the transverse axis where other stresses are also maximum.
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