Designing Rectangular Columns in STAAD Pro - RAM | STAAD Forum - RAM | STAAD - Bentley Communities

### Designing Rectangular Columns in STAAD Pro

I noticed that when we design a rectangular column, STAAD Pro always arrange the reinforcements as equal number on each face ? I ask the instructor who teach us at Bentley and he didnt have an answer.

### 5 Replies (Most Recent Reply)

• Not sure which code you are referring to. But for most codes, STAAD designs columns by placing equal number of bars on all 4 faces. For some codes like the Indian code, there is a parameter to specify if the bars should be just on 2 faces.

ACI-318-05 Code.I think that whatever you do, STAAD Pro can not handle unequal arrangement of bars.

check this output file:

****************************************************

*                                                                                    *

*           Version  20.07.06.35                                    *

*           Proprietary Program of                                 *

*           Bentley Systems, Inc.                                   *

*           Date=    OCT  3, 2010                                   *

*           Time=    20:34:35                                          *

*                                                                                     *

*      USER ID: ***************************               *

****************************************************

2. START JOB INFORMATION

3. ENGINEER DATE 03-OCT-10

4. END JOB INFORMATION

5. INPUT WIDTH 79

6. UNIT FEET KIP

7. JOINT COORDINATES

8. 1 0 0 0; 2 0 10 0

9. MEMBER INCIDENCES

10. 1 1 2

11. DEFINE MATERIAL START

12. ISOTROPIC CONCRETE

13. E 453600

14. POISSON 0.17

15. DENSITY 0.150336

16. ALPHA 5E-006

17. DAMP 0.05

18. END DEFINE MATERIAL

19. MEMBER PROPERTY

20. 1 PRIS YD 3.28084 ZD 0.984252

21. CONSTANTS

22. MATERIAL CONCRETE ALL

23. SUPPORTS

24. 1 FIXED

27. 2 MX 100

28. PERFORM ANALYSIS

STAAD SPACE                                              -- PAGE NO.    2

P R O B L E M   S T A T I S T I C S

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

NUMBER OF JOINTS/MEMBER+ELEMENTS/SUPPORTS =     2/     1/     1

SOLVER USED IS THE OUT-OF-CORE BASIC SOLVER

ORIGINAL/FINAL BAND-WIDTH=     1/     1/      6 DOF

TOTAL PRIMARY LOAD CASES =    1, TOTAL DEGREES OF FREEDOM =      6

SIZE OF STIFFNESS MATRIX =        1 DOUBLE  KILO-WORDS

REQRD/AVAIL. DISK SPACE  =     12.0/ 327276.8 MB

29. START CONCRETE DESIGN

30. CODE ACI

31. MAXMAIN 10 ALL

32. DESIGN COLUMN ALL

STAAD SPACE                                              -- PAGE NO.    3

====================================================================

COLUMN  NO.     1  DESIGN PER ACI 318-05 - AXIAL + BENDING

FY - 60000  FC - 4000 PSI,  RECT SIZE - 11.81 X 39.37 INCHES, TIED

AREA OF STEEL REQUIRED =   6.929  SQ. IN.

BAR CONFIGURATION       REINF PCT.   LOAD   LOCATION   PHI

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

12 - NUMBER  7           1.548        1      END     0.650

(PROVIDE EQUAL NUMBER OF BARS ON EACH FACE)                 ???????

TIE BAR NUMBER    4 SPACING  11.81 IN

********************END OF COLUMN DESIGN RESULTS********************

33. END CONCRETE DESIGN

34. FINISH

• In reply to Ahmed Shakir:

For column design per the ACI code, STAAD offers only an arrangement that involves equal bars on all 4 faces.

• In reply to Geeky biswa:

I think this should be written beside the message :

(PROVIDE EQUAL NUMBER OF BARS ON EACH FACE)

by saying:

Note that: For current release, STAAD CAN ONLY ARRANGE COLUMNS BARS AS EQUAL NUMBER ON ALL 4 FACES.

in that way when STAAD somtimes said that there is no possible arrangemnet for bars, that not necessarlly lead to wrong design so one should increase the column size but one should check other arrangments that STAAD can not handle.

• In reply to Ahmed Shakir:

Mr. Ahmed Sh is right. Some change in Staad make engineer happier ever after, I think.