Boltpreload and displacement in contact

[Protte]

Hello all,

Im working on a way to simulate a bolt contact with the sol101. For sol 601 I don’t have the license. In most cases its working for my problems well. But found a problem if I use friction to stop movement. I can see a small displacement in my connection. To check this I build this small model. Bolt preload is on a beam, which is connected by RB2 to the soild. The solids are connected by a linear connect:

Checked:
- node constraints on rot
- different rigids (rot)
- different boltfacts,
- and some more

Picture of the model:

Picture of the results (only bolt preload and with load):

my model if some want to try:

http://h2107735.stratoserver.net/protte/FEM/PB.modfem

may some have a clue how to fix it and make a stable connection.

 

[stressebookllc]

Sol 101 will simply weld the contact regions, that is my understanding.. Because you are using RBE2, any displacement of the independent node of the RBE2 connecting the beam element node at the top of the shank to the head will move the head by the same amount. The deformation you are seeing may simply be elastic glued deformation magnified.

http://www.stressebook.com

Stressing Stresslessly!

 

[Protte]

The sol101 has two different types of connection. Linear connection and glued. I used the first one. The second one has no traction on the contact region. But you bring me on another idea. To get the preload of 10KN we have to deform our beam about 0,012mm (dl=F*l/(EA)). My deformation in independent node is :

Node 10419
  Output Set        8 : BP ONLY 10kn
        Value =        0.036456  |  Output Vector        1 : Total Translation
        Value =        0.011525  |  Output Vector        2 : T1 Translation
        Value =         0.02153  |  Output Vector        3 : T2 Translation
        Value =        0.027068  |  Output Vector        4 : T3 Translation
  Output Set        9 : BP ONLY 20KN
        Value =        0.075214  |  Output Vector        1 : Total Translation
        Value =         0.02305  |  Output Vector        2 : T1 Translation
        Value =         0.04319  |  Output Vector        3 : T2 Translation
        Value =          0.0571  |  Output Vector        4 : T3 Translation

we see total deformation is 3*T1. T1 is the axial vector of my bolt. But if i set a friction in my connection. there should be no traction in my connection.

 

[BlasMolero]

Hello!,
The link to donwload the FEMAP model is not valid, something is wrong, please check.
Best regards,
Blas.

~~~~~~~~~~~~~~~~~~~~~~
Blas Molero Hidalgo
Ingeniero Industrial
Director

IBERISA
48004 BILBAO (SPAIN)
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http://www.iberisa.com

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