VM-WB-MECH-090

VM-WB-MECH-090
Delamination Analysis of a Double Cantilever Beam Using Interface Delamination

Overview

Reference: Alfano, G., & Crisfield, M. A. (2001). Finite element interface models for the delamination analysis of laminated composites: Mechanical and computation issues. International Journal for Numerical Methods in Engineering, 50, 1701-1736.
Solver(s):

Ansys Mechanical

Analysis Type(s):

Static Structural

Element Type(s):

Solid

Test Case

A double cantilever beam of length l, width w, and height h with an initial crack of length a at the free end is subjected to a maximum vertical displacement Umax at the top and bottom free end nodes. Determine the vertical reaction at point P based on the vertical displacement for the interface model.

This problem is also presented in

VM248

in the Mechanical APDL Verification Manual.

Figure 121: Double Cantilever Beam Sketch

Double Cantilever Beam Sketch

Material PropertiesGeometric PropertiesLoading
Composite
E11 = 135.3 GPa
E22 = 9.0 GPa
E33 = 9.0 GPa
G12 = 5.2 GPa
ν12 = 0.24
ν13 = 0.24
ν23 = 0.46
Interface
C1 (maximum stress) = 25 MPa
C2 (normal separation) = 0.004 mm
C3 (shear separation) = 1000 mm
l = 100 mm
a = 30 mm
h = 3 mm
w = 20 mm

Umax = 10 mm

Analysis Assumptions and Modeling Notes

A double cantilever beam is analyzed under displacement load using interface elements for delamination and 2-D plane strain formulation elements. An imposed displacement of Uy = 10 mm acts at the top and bottom free vertex.

An Interface Delamination object is inserted to model delamination.

Equivalent material constants are used for the interface material, as Mechanical uses the exponential form of the cohesive zone model and the reference uses a bilinear constitutive model.

Results Comparison

Lower Order Results
 TargetMechanicalError (%)
Max RFORCE and corresponding DISP:
RFORCE FY (N)60.0060.0690.115
DISP UY (mm)1.001.0000
End RFORCE and corresponding DISP
RFORCE FY (N)24.0023.966-0.142
DISP UY (mm)10.0010.000
Higher Order Results
 TargetMechanicalRatio
Max RFORCE and corresponding DISP
RFORCE FY (N)60.0060.0630.105
DISP UY (mm)1.001.0000
End RFORCE and corresponding DISP
RFORCE FY (N)24.0023.966-0.142
DISP UY (mm)10.0010.000