Evaluation of Thin Kevlar-Epoxy Fabric Panels Subjected to Shear Loading

Technical Report · Mon Apr 01 04:00:00 EST 1996

OSTI ID:382974

Baker, D J

The results of an analytical and experimental investigation of 4-ply Kevlar-49-epoxy panels loaded by in-plane shear are presented. Approximately one-half of the panels are thin-core sandwich panels and the other panels are solid-laminate panels. Selected panels were impacted with an aluminum sphere at a velocity of either 150 or 220 ft/sec. The strength of panels impacted at 150 ft/sec was not reduced when compared to the strength of the undamaged panels, but the strength of panels impacted at 220 ft/sec was reduced by 27 to 40 percent. Results are presented for panels that were cyclically loaded from a load less than the buckling load to a load in the postbuckling load range. The thin-core sandwich panels had a lower fatigue life than the solid panels. The residual strength of the solid and sandwich panels cycled more than one million cycles exceeded the baseline undamaged panel strengths. The effect of hysteresis in the response of the sandwich panels is not significant. Results of a nonlinear finite element analysis conducted for each panel design are presented.

• Research Organization: Army Research Lab., Hampton, VA (United States)
• OSTI ID: 382974
• Report Number(s): N--96-24084; NASA-TM--111457; NAS--1.15:111457; AIAA-Paper--96-1367; NIPS--96-43737
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
BUCKLING
EPOXIDES
FINITE ELEMENT METHOD
HYSTERESIS
IMPACT STRENGTH
IMPACT TESTS
MATRIX MATERIALS
PANELS
SHEAR PROPERTIES
SOLIDS
STRAIN GAGES