An Equivalent Radius Model (ERM) for the prediction of compressive strength reduction in laminates with molded-in holes is presented. This model replaces a molded-in hole panel by an equivalent drilled hole panel with the same notched strength. As a result, the ERM relies on an accurate stress failure criterion for drilled hole panels. The experimental results obtained from woven carbon fiber/epoxy laminates with molded- in and drilled holes indicate that the proposed model satisfactorily simulates the observed strength behavior. It is believed that the simplicity of the present model coupled with its accuracy and generality makes it of practical value to the design engineers.
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