Experimental Mechanics

, Volume 17, Issue 7, pp 265–270 | Cite as

Direct determination of interlaminar stresses in polymeric adhesive layer

An experimental method is presented for determination of stresses along the interlaminar adhesive layer, embedded within a double model. Measured data are compared with available analytical solutions
  • O. Ishai
  • D. Peretz
  • S. Gali
Article

Abstract

A method for direct measurement of shear and normal displacements, and a simple way of determining the distribution of the respective average stresses along an interlaminar adhesive layer (IAL), were successfully examined on a symmetrical doubler model. Experimental data proved to be in agreement with available analytical solutions for this model in the elastic stage. The method was also examined beyond the elastic linear range and may be used to follow up the initiation of delamination.

Keywords

Experimental Data Mechanical Engineer Fluid Dynamics Direct Measurement Average Stress 

Nomenclature

A, B, C, r

constants

b

width

c

half length of IAL

E0,E1,E2, (Ei)

Young's moduli of IAL, CAL and EAL, respectively

F

axial applied force per unit width

G0

shear moduli of IAL

h0,h1,h2

thickness of IAL, CAL and EAL respectively

M

moment function along the EAL

N

normal force along the EAL

pc

effective applied axial normal stress

p0

reference axial stress (acting on EAL midpoint under uniform axial strain)

u

displacement in thex direction

V

shear force along the EAL

w

displacement in thez direction

x, y, z

axial, transverse and lateral coordinates, respectively

α, β, γ

coefficients

\(\tau _{zx}^{(0)} = \tau _0 \)

axial shear stress (in thex direction) acting at the IAL

τ*

nondimensional axial shear stress acting at the IAL

\(\sigma _x^{(1)} ,\sigma _x^{(2)} \)

longitudinal normal stresses acting at the CAL and EAL, respectively

\(\sigma _z^{(0)} = \sigma _0 \)

lateral normal stress (in thez direction) acting at the IAL

σ*

nondimensional lateral normal stress acting at the IAL

χ

nondimensional axial coordinate

MMD

multimaterial doubler

IAL

interlaminar adhesive layer

CAL

central adherend layer

EAL

external adherend layer

FRP

fiber-reinforced plastics

SLJ

single-lap joint

DLJ

double-lap joint

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References

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Copyright information

© Society for Experimental Mechanics, Inc. 1977

Authors and Affiliations

  • O. Ishai
    • 1
  • D. Peretz
    • 2
  • S. Gali
    • 3
  1. 1.Faculty of Mechanical EngineeringHaifaIsrael
  2. 2.Faculty of Mechanical EngineeringHaifaIsrael
  3. 3.Technion Israel Institute of TechnologyHaifaIsrael

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