TEST CASE 6.2 SYSTEM WITH SINGLE-SIDE SPRINGS
Reference:
А. В. Перельмутер, В. И. Сливкер. Расчётные модели сооружений и возможность их анализа, Киев: «Сталь», 2002, стр. 123.
Problem description:
An absolutely rigid body has a form of a square with sides, located along the coordinate axes. It is braced at corners via five identical tensile only springs. A concentrated force P is applied perpendicular to the middle of the left side of the absolutely rigid body square. Determine the reactions forces in the springs R.
Problem sketch:
Type of created problem:
Plane truss or beam-wall (X, Z).
Geometric characteristics:
L = 20 m.
Material properties:
Stiffness of one-sided links: EA/L = 1·108 tf/m.
Boundary conditions:
Spring fixation points: X = Z = 0.
Loads:
P = 10 tf.
Model description:
The system is modeled by 1 plate finite element of plane stress (FE type is 27) and 5 physically nonlinear bar FE of one-sided inelastic links (FE type is 265). For nonlinear solution iterative process is used (number of steps is 1, minimum number of iterations is 300).
Calculation results:
Target value |
Theoretical solution |
LIRA 10 |
Deviation, % |
R1, tf |
12.44 |
12.44 |
0.00 |
R2, tf |
0.893 |
0.89313 |
0.01 |
R3, tf |
5.77 |
5.7735 |
0.06 |
R4, tf |
0.00 |
0.00 |
0.00 |
R5, tf |
0.00 |
0.00 |
0.00 |