Learning Forum

[Arthur Soulie]

Hello everyone,

I am doing a simple model of single bolted joint which is clamping 2 plates together.

The problem is that after applying the pretension in the first step, locking it in the subsequent step and finally apply a an axial force on the plates results get physically incoherent.

The workload I extract from the simulation with the bolt tool is either below pretension value or exactly the value of the applied external load.

I have hand calculated the fraction of external load carried by the bolt and it should be about 24 % which is very far from what I get.

I am using an M10 bolt made up in Standard Steel Non-linear and Aluminium Alloy Non-linear for plates, I activated NLGEOM in analysis settings went through tutorials which describe the same geometry as mine and still it doesn't work.

I have used  the same principle than in this video: Mechanics of Bolted Connections — Lesson 2, Part 3 - YouTube

I have changed boundary conditions many time, geometry and so on, still I have the same problem with the workload of the bolt which doesn't seem to care about the external load I apply, nothing from it is transferred into the bolt.

I'd be glad to here from you people about that issue, thanks for considering my request.

Arthur 

[Ashish Khemka]

Hi Arthur,

 

Why do you get the preload the same as the applied load? Are the plates separating? Can you please check the contact status between the plates?

 

Regards,

Ashish Khemka

[mrife]

Hi Arthur

In addition to what Ashish said I'd like to add check if there is any contact between the bolt shank and the plates hole areas.  Sounds like maybe bonded contact got defined there.

Mike

[Arthur Soulie]

Hi,

There is not contact between the bolt shank and the plate holes since in the geometry the holes are larger than the bolt shank.

In what concerns the contact status between the two plates, in the last loading I have used there is no contact between the two plates (pressure = 0). But in the previous load cases contact was still operating but the results in the workload weren't good anyway.