Use of least-square extrapolation and local stress smoothing of interlaminar stresses in composite laminates

Conference · Sat Dec 31 04:00:00 EST 1994

OSTI ID:89884

Shah, D K; Chen, D J; Chan, W S ^[1]

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1. Univ. of Texas, Arlington, TX (United States). Center for Composite Materials

This paper applies the finite element least-square extrapolation and smoothing technique to demonstrate its advantages in evaluation of interfacial stress distributions in composite laminates. The analysis uses the quasi-3D finite element modeling technique and complete 3-D analysis using ABAQUS to investigate the stress distributions in graphite/epoxy laminates. Linear (2 point integration) and quadratic (3 point integration) least square fits in 8-node quadrilaterals and 20 node solid isoparametric elements are demonstrated. The evaluation of transformation matrix from gaussian stresses to nodal stresses was performed using symbolic mathematics on `Mathematica`. The results show that use of extrapolation and smoothing offer better estimates of stress distributions and the interfacial stresses in composite laminates.

• OSTI ID: 89884
• Report Number(s): CONF-9409291--; ISBN 1-56676-220-0
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
BOUNDARY CONDITIONS
CARBON FIBERS
COMPOSITE MATERIALS
EPOXIDES
FINITE ELEMENT METHOD
INTERFACES
MATHEMATICAL MODELS
STRESS ANALYSIS
STRESSES
THREE-DIMENSIONAL CALCULATIONS