Bearing loads and constraints in a plate

[sift]

Hello-

I'm a novice abaqus user. I'm trying to model a plate that:
* is suspended vertically
* has holes across the top
* and one hole on the bottom
* cables run thru the upper holes, securing the plate
* a pin runs thru the bottom hole, applying the load.
* (imagine something like a crane, suspending a plate that a load is attached to).

I need to analyze stresses in the plate. These are bearing loads/constraints.

*LOADS: I've approximated the bearing load as a uniform pressure applied to half of the bottom hole
* BCs: I've held the upper half of the upper holes with encastre constraints.

My problem is this: I'm getting big stress concentrations at lateral sides of the constraint holes, at the boundaries of the partition.

Is there a better way to model bearing constraints and bearing loads?

 

[corus]

For the perssure load a better way is to apply a sinosoidal pressure for which the nett load is equal to your applied load.
To avoid the large stresses at the restraints you could calculate the load that would be applied there and apply a pressure load as described above, and then restrain the body elsewhere to prevent rotation and translation. If you have all the loads applied correctly then you would see zero reaction force at that position. Alternatively you could model the pin and use contact, restraining the pin. That would give you a 'soft' restraint at the pin hole.

Tata

 

[sift]

Thanks corus. How do i define a sinusoidal load? My understanding is that i have to define an analytical field; is that right? I'm not sure how to set up the variables and coordinate system. Any ideas?

 

[sift]

Okay- I created a sinusoidal pressure load. I figured out how to define an analytical field but still don't know what constants to use. Right now, my field is 2*sin(TH), relative to a cylindrical coord sys I created. I don't know if that equation is correct though.

What equation/constants should I use for defining the sinusoidal pressure?

 

[ESPcomposites]

Assuming you can get a good stress field around the hole, what do you want to do with this information?

Brian

http://www.espcomposites.com