#1 2017-06-07 00:31:08

Humberto

Member

From: Ensenada, Mexico

Registered: 2012-10-15

Posts: 99

Website

What is the correct way to model contact with a fastener (preload)

I was just wondering how to model a fastener as this guy did in here.

h ttps://youtu.be/VA0eg0LWfWM

I think You define your contact, master and slave surfaces, but then how do you set the fastener and its pre load.

Do we have anything like that in Code Aster?

just Curious

Regards.

pierre_j

Member

Registered: 2010-01-19

Posts: 773

Re: What is the correct way to model contact with a fastener (preload)

Hello,

I am absolutely not familiar with this type of modelling.
However, this article briefly speaks about it:
//www.code-aster.org/spip.php?article617

In this article, test case ssnv228 is mentionned as an example.

Good luck.
Best regards,

Pierre

reiteres

Member

Registered: 2013-06-03

Posts: 560

Re: What is the correct way to model contact with a fastener (preload)

As far as I know there is no straight forward way to apply a preload. The easist trick is to add a suitable beam Element and

1) Compute the resulting Force/Stress of the preload first. There are formulas for that,
2) Apply a temperature Load on the beam to simulate the tightening. To get the correct temperature
we use the Formulas

σ = E ϵ = α T,

and hence

T = E ϵ/α = σ/α

at least that's what I'm doing to perform a simple preloading.
Here is an old example how it can be done: code-aster.org/forum2/viewtopic.php?id=14375

Last edited by reiteres (2017-06-20 09:34:07)

Humberto

Member

From: Ensenada, Mexico

Registered: 2012-10-15

Posts: 99

Website

Re: What is the correct way to model contact with a fastener (preload)

Thanks for both of you... I will dig into it.