How to prevent tension columns in designing by RCDC and Staad Pro.

  1. 0842.House.std File attached. Is there any way in Staad pro and RCDC both so that the final designing of any column should NOT be as "Tension Columns"?
  2. I want so because when the column is designed as tension column (on its own) then its % reinforcement is higher then the % reinforcement of the column below.
  3. I repeated this experiment on a simplest structure with only four symmetric column and 2 floors still I got one column of upper floor as tension column hence with more reinforcemwnt as compared to other 7 columns which seems extremely odd. 
  4. Although this issue got resolved on increasing the section of column (to a certain limit only because beyond that it again becomes a tension column) or by increasing the grade of steel (which was way  too much).

So please suggest me how to ignore staad pro and RCDC mainly to prevent column design as tension column. Means non of the upper floor columns should have higher reinforcement then lower floor column.....

This tension column is really giving me tension and making my BBS absurd....

I use IS 456 which doesn't have tension column still rcdc and staad pro gives so...

Please help me

Thankss.

  • Hi,

    Kindly share your RCDC file for further study. 

    Thanks.

    1. This is that STAAD Pro File....House.std
    2. Ive uploaded the file as per your advice... You can see that Column no. 30 of Ground floor which is just below column no. 75 of 1st floor. C75 have more % reinfm than C30. I know that Moment of C75 is more than C30 that's why its having more reinforcement. And I know it can be resolved by increasing the section of both columns or simply copy down the bars of upper column 75 to lower column 30...
    3. But I want something else if there is anything else possible so that staad pro does not consider it as tesion column because Im using RCDC after analysis in Staad Pro.
    4. This issue of tension column prevails even in every and most simple structures with 4 columns only. Even there is a particular range I found while incresding the section within which the upper floor column has same/less reinforcement than lower column, but beyond or below that range of cross section, upper column was acting as tension column...
    5. Any suggestions are appreciated.
    6. Regards....