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Good Night, 

My name is ingrid and I am trying modelling one ring of linning tunnel in Abaqus, the last mont I tried in sap2000 but i could not hav good answer., for this reason i am doing my model in Abaqus with only springs radials (in the moment).

Anyone could help me? About how input the loads, Is better radial or vertical and horizontal. 

Thanks you.

Regards,

Ingrid

 

Modelo_Abaqus!.JPG

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Hi Ingrid,

Please check out the following topics as the starting point:

There is discussion about loading on the above mentioned topic. Also, please get in touch with @Hira Malik as I believe she is actively designing tunnels and would be better able to guide you in this regard.

Thanks.

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9 minutes ago, UmarMakhzumi said:

There is discussion about loading on the above mentioned topic. Also, please get in touch with @Hira Malik as I believe she is actively designing tunnels and would be better able to guide you in this regard.

She is already in contact with me :). But unfortunately I had to get involved on another project, leaving the tunnel design as it was. Still I have shared all the stuff I had with her. I was hoping we have a tunnel design expert here in the group. Really needed.

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1 minute ago, Hira Malik said:

She is already in contact with me :). But unfortunately I had to get involved on another project, leaving the tunnel design as it was. Still I have shared all the stuff I had with her. I was hoping we have a tunnel design expert here in the group. Really needed.

I will ask out to see if we can get someone experienced in Tunnels. The problem is not a lot of people are willing to dedicate time to this. But, will give it a shot.

Thanks.

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On 2018-03-15 at 10:46 AM, ingrid rocio irreño palomo said:

I am need the sofware Straus 7, Can help me?

Sorry, its against our forum policy to share software download links.

Thanks.

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    • Dear All,

      The forum has been updated today with a lot new features.

      You can find the list of all the new improvements by visiting this website.

      Some highlights are:

      1) Improved Search Features


      2) Emoji

      Emoji support is now available in all editors.


      Do check out the link posted above for the complete list.

      One additional announcement that I would like to make is that with reference to last forum update post (read below),  @Rana and @BAZ are forum Admins now. I think it was important to do as it brings more transparency for the forum and also helps spread the responsibility. The forum belongs to the members so it never made sense for one person to be Admin,

      As always, feedback is much appreciated.

      Thanks for taking the time out to read this update.

      Cheers!

       
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    • Hi guys just to discuss with you my understanding of crack widths in Environmental structures according to ACI. 

       

      ---------------------------

      Normal structures

      ---------------------------

       

      1. ACI 318-95 based on statistical method of Gergely & Lutz 1968 limits Z based on exposure. We are calculating crack widths here. (Normal structures)

       

      2. ACI 318-99 proposed limiting the spacing and removed actually calculating the width and also removed the exposure conditions. For example for beams and one-way slabs s (in) = 540/fs -2.5cc or in other words limiting the fs=0.6fy  (For normal structures)

       

      3. ACI 224R-01 references method 1 and 2 above and 3 european codes.

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      ---------------------------

      Water tight structures

      ---------------------------

       

      1. ACI 318-08 states clearly that for watertight structures ACI 350-06 codes should be used. 

       

      2. ACI 224.4R-13 also specifically states that for watertight structures walls in section 7.4, we should use ACI 350-06. 

       

      3. ACI 350-06 for water tight structures does not recommend calculating a number for crack width but rather limiting max steel stress in bars to be 20k ksi or fs=0.33fy for normal conditions.

       

      ---------------------------------------------------------------------------------------------------------

      To sum it up, 

       

      Philosophy of crack width control is not to calculate probable crack widths but to limit the max stress in steel bars.

       

      For normal structures: fs=0.6fy and for water tight structures fs=0.33fy
      • 1 reply
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    • Material behavior can be idealized as consisting of an 'elastic' domain and a 'plastic' domain. For almost 200 years, structural design has been
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      • 0 replies
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      Good Night, 
      My name is ingrid and I am trying modelling one ring of linning tunnel in Abaqus, the last mont I tried in sap2000 but i could not hav good answer., for this reason i am doing my model in Abaqus with only springs radials (in the moment).
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      Ingrid
       
       

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