You are being redirected because this document is part of your ASTM Compass® subscription.
    This document is part of your ASTM Compass® subscription.


    Determination of Ply-Drop Configurations

    Published: Jan 1993

      Format Pages Price  
    PDF (184K) 10 $25   ADD TO CART
    Complete Source PDF (7.8M) 10 $110   ADD TO CART


    Unidirectional glass/epoxy tapered specimens were manufactured and tested under static tension and tension-tension fatigue. Four different ply-drop configurations are studied with either grouped or dispersed plies and either staircased or overlapped dropped plies. At damage events in the static tests and at prescribed numbers of cycles in the fatigue tests, the specimens were placed in a cantilever fixture to determine their bending stiffnesses. The static tests indicated that the staircased-grouped and dispersed-overlapped specimens exhibited preferred structural performance by retaining their bending stiffness up to failure. The dispersed-overlapped specimen exhibited stable delamination growth. In addition, the fatigue tests indicated slow growth in the dispersed-overlapped with corresponding losses in the bending stiffness.


    delamination, ply-drop, static tension, fatigue, bending stiffness

    Author Information:

    Fish, JC
    Research engineer, Lockheed Advanced Development Company, Sunland, CA

    Vizzini, AJ
    Associate professor, University of Maryland, College Park, MD

    Committee/Subcommittee: D30.04

    DOI: 10.1520/STP12637S

    CrossRef ASTM International is a member of CrossRef.