Learning Forum

[ik356]

Hi all,

I have modeled an arch (BEAM188) which ends are supported by springs(COMBIN14). The arch is modeled between key points K#1 & K#2. One spring is connected between the key points K#1 & K#3 and the other spring is connected between the key points K#2 & K#4. The Uniform distribution of unit compressive pressure is applied on arch in the radial direction. Now the total system is the Global cylindrical system. K#1 & K#2 are constrained in all DOFs except in radial direction and K#3 & K#4 are constrained in all DOFs.

Eigenvalue buckling analysis has been done in ANSYS APDL. The buckling shape(blue line) is shown in the below figure.

I don't want the displacement at the key points K#1 & K#2 for creating the physical model of the system.

It means the effect of the stiffness value of spring should be considered without any displacement at the key points K#1 & K#2.

What should be done to avoid the compression and stretching of the spring displacements at key points K#1 and K#2 ?

Kindly, someone can help me by adding the effect of the stiffness value of spring without getting any displacements at the keypoints K#1 & K#2.

Thanks & Regards

[Sheldon Imaoka]

Hi,

When you mention the following:

I don't want the displacement at the key points K#1 & K#2 for creating the physical model of the system. 

It means the effect of the stiffness value of spring should be considered without any displacement at the key points K#1 & K#2.  

could you provide more clarification?  If you don't want displacement at points K1 and K2, then you wouldn't want to use a spring since a spring does have some movement.

Is your COMBIN14 defined as a 3D longitudinal spring, or is it defined as a 1D spring (spring acting only in 1 direction, such as radial direction if nodal coordinate systems on both ends are oriented correctly)?  What is your spring stiffness?

If you don't want compression/stretching of the springs at K1 and K2, why do you have a spring defined?  Why not just constrain the nodes radially?

Regards,
Sheldon