Bolt with failure

Raphael_22515
Raphael_22515 New Altair Community Member
edited October 2020 in Community Q&A

Hi there,

 

 

I'm currently working on a bolt model for blast simulations on bolted plates.

The model is quite simple rigid spiders(RB2) at the head and nut end and a spring element in between.

The spring is pretensionned using a type 32 property (/PROP/TYPE32 (SPR_PRE)).

 

I'd like to represent the spring failure based on positive rupture displacement but the property doesn't include this unlike /PROP/TYPE4 (SPRING).

I'm having trouble finding how to include this criterion in the TYPE32 (SPR_PRE) property.

Despite some time spend on tutorials and looking in the theory manual I didn't find what I was looking for.

 

 

So my question is the following : How can i both include a pretension in the spring and apply a failure criterion ?

 

 

Best regards,

 

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Answers

  • Altair Forum User
    Altair Forum User
    Altair Employee
    edited July 2013

    Maybe this 'trick' is of some help to you: For function ID1 in the PROP/32 Input, define zero force values after the critical elongation, so that for greater displacements than the critical elongation of the spring it deforms without resistance

  • Raphael_22515
    Raphael_22515 New Altair Community Member
    edited July 2013

    First thx for your reply florian.

     

    The trick you exposed is quite simple, altough it doesn't represent properly failure it is efficient.

    The problem is that the elongation of the spring to set the pre-load is negative so the max eps of the spring at rupture in use doesn't reach 0.