Strain State of a Split Circular Ring Subjected to Two Mutually Perpendicular Forces Px and Py, Acting in the Plane of the Ring

Objective: Strain state of a split circular ring under bending in the plane without taking into account the transverse shear deformations.

Initial data file: 4_6.spr

Problem formulation: The split circular ring is subjected to two mutually perpendicular forces Px and Py, acting in the plane of the ring axes. Determine the strain state of the ring.

References: Strength Analysis in Mechanical Engineering / S. D. Ponomarev, V. L. Biderman, K. K. Likharev, et al., In three volumes. Volume 1. M.: Mashgiz, 1956.

Initial data:

E = 2.0·1011 Pa - elastic modulus;
R = 1.3 m - radius of the ring axis;
F = 1·10-2 m2 - cross-sectional area;
I  = 5·10-6 m4 - cross-sectional moment of inertia;
Px = Py = 1 kN - value of the concentrated force.
 

 

Finite element model: Design model – plane model, 120 bar elements of type 2, 121 nodes.

Results in SCAD


Values of displacements u (mm)


Values of displacements  v (mm)

Comparison of solutions:

Angle φ, degree

Displacements along the x axis

Displacements along the y axis

Theory

SCAD

Deviations, %

Theory

SCAD

Deviations, %

0

-6.902

-6.900

0.03

-20.706

-20.703

0.01

45

2.690

2.691

0.04

-16.777

-16.774

0.02

90

6.275

6.275

0.00

-8.472

-8.470

0.02

135

3.984

3.984

0.00

-2.419

-2.417

0.08

180

0.943

0.942

0.11

-0.943

-0.941

0.21

225

0.154

0.153

0.65

-1.125

-1.124

0.09

270

0.316

0.315

0.32

-0.627

-0.627

0.00

315

0.114

0.114

0.00

-0.074

-0.075

1.35

360

0.000

0.000

0.00

0.000

0.000

0.00

 

Notes: In the analytical solution the displacements of the points of the ring in the directions x and y are determined according to the following formulas:

\[ u\left( \phi \right)=\frac{P_{x} \cdot R^{3}}{E\cdot I}\cdot \beta_{1} \left( \phi \right)+\frac{P_{y} \cdot R^{3}}{E\cdot I}\cdot \beta_{2} \left( \phi \right), \] where: \[ \beta_{1} \left( \phi \right)=-0.5\cdot \left( {2\cdot \pi -\phi } \right)-\sin \left( \phi \right)+0.5\cdot \sin \left( \phi \right)\cdot \cos \left( \phi \right); \] \[ \beta_{2} \left( \phi \right)=1+\left( {2\cdot \pi -\phi } \right)\cdot \sin \left( \phi \right)-\cos \left( \phi \right)+0.5\cdot \sin^{2}\left( \phi \right); \] \[ v\left( \phi \right)=\frac{P_{x} \cdot R^{3}}{E\cdot I}\cdot \gamma_{1} \left( \phi \right)+\frac{P_{y} \cdot R^{3}}{E\cdot I}\cdot \gamma_{2} \left( \phi \right), \] where: \[ \gamma_{1} \left( \phi \right)=-1+\cos \left( \phi \right)+0.5\cdot \sin ^{2}\left( \phi \right); \] \[ \gamma_{2} \left( \phi \right)=-0.5\cdot \left( {2\cdot \pi -\phi } \right)-\left( {2\cdot \pi -\phi } \right)\cdot \cos \left( \phi \right)-\sin \left( \phi \right)-0.5\cdot \sin \left( \phi \right)\cdot \cos \left( \phi \right). \]