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Author Topic: BJSFM Analysis - Sandwich Panel Edge Splice Joint  (Read 5019 times)

Rocketman007

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BJSFM Analysis - Sandwich Panel Edge Splice Joint
« on: July 08, 2009, 07:57:28 AM »
Hypersizer V5.7.6 (Question Submitted on Behalf of Goodrich Aerostructures)

The Hypersizer BJSFM analysis applicability is primarily for solid laminate joints. The load in the solid laminate shell element is representative of the bypass load at the joint. Most Aerospace companies prefer joints at solid laminate locations. In some cases bond panels (Two face sheets and a honeycomb core) do have bolted joints, but there are many issues. Bolted joints on honeycomb panels are primarily used on secondary structures.

If a BJSFM analysis is conducted at a bond panel joint a potential issue occurs. If we splice a metal fitting at the edge of a bond panel, the BYPASS load may not be correct. This potential error is a function of the Nastran shell element load assumptions. Axial load is divided equally by the two face sheets (If similar face sheets) in the Nastran shell element. At the edge splice joint  100% of the axial load is transferred from the face sheet with the splice material attached on one side of the bond panel.

Question:

Is Hypersizer BJSFM analysis with shell elements appropriate for a bond  panel edge and a splice joint, and if not is there a potential work around.

Would it be more appropriate to model a bond panel with solid elements if a joint analysis is required. The BJSFM analysis would recover the correct face sheet Bypass load in the laminate attached to the splice.