Ansys Workbench-Chapter10

1. Chapter 10 Buckling and Stress Stiffening 1
Chapter 10
Buckling and Stress Stiffening
10.1 Step-by-Step: Stress Stiffening
10.2 Step-by-Step: 3D Truss
10.3 More Exercise: Beam Bracket
10.4 Review

2. Chapter 10 Buckling and Stress Stiffening Section 10.1 Stress Stiffening 2
Section 10.1
Stress Stiffening
Problem Description
1000 mm
P
[1] The beam is made of
steel and has a uniform
cross section of 10x10 mm.
[2] A uniformly distributed
load of 0.1 N/mm applies
downward on the beam.
[3] An axial force applies
on the beam's end that is
free to move horizontally.

3. Chapter 10 Buckling and Stress Stiffening Section 10.1 Stress Stiffening 3
3
4
5
6
7
8
9
10
-500 0 500 1000
MaximumDeflection(mm)
Axial Force (N)
Stress Stiffening Effects
This is the point with zero axial
force. On the right, the beam is
subject to tensile force. On the
left, the beam is subject to
compressive force.

4. Chapter 10 Buckling and Stress Stiffening Section 10.1 Stress Stiffening 4
Linear Buckling Analysis

5. Chapter 10 Buckling and Stress Stiffening Section 10.1 Stress Stiffening 5

6. Chapter 10 Buckling and Stress Stiffening Section 10.2 3D Truss 6
Section 10.2
3D Truss
Problem Description
Pbuckling
=
π2
EI
L2
=
π2
(29,000,000)(0.13852)
(133.46)2
= 2,226 lb = 0.14P

7. Chapter 10 Buckling and Stress Stiffening Section 10.2 3D Truss 7
Results
Buckling will occur
when 23% of design
loads apply on the
structure. The
multiplier can be viewed
as safety factor. The
structure is not safe.

8. Chapter 10 Buckling and Stress Stiffening Section 10.3 Beam Bracket 8
Section 10.3
Beam Bracket
Problem Description
[3] Compressive
stress at the
web.
• It is a good practice that an
engineer always checks the
structural stability whenever
compressive stresses exist.

9. Chapter 10 Buckling and Stress Stiffening Section 10.3 Beam Bracket 9
Results
The <Load
Multiplier> can be
viewed as a safety
factor. It predicts
that 203 times of
design load will
initiate a buckling.
The structure is
safe.