Indian Code - Steel Column Design

Dear Sir,

   It appears you have given the joint load at a pinned support. In that case, the load will directly go to the support and no load will go to the member. Hence, even if you increase the load, you are not getting changed result... Effective load on the section is only the selfweight...

Arun

Dear Arun,

The last two lines in command/input file i.e. PARAMETER 3, CODE INDIAN is in any way going to change the design. Is it not that input up to the line prior to the above is adequate to complete the design? This query is for my personal satisfaction.

Dany:

Arun is correct.  The concentrated load is applied to a node which is pinned. Hence, all the concentrated load will flow to the pinned support, leaving the column section to wothstand only the load due to selfweight.

Suresh:

The last two lines are unnecessary. You will have the same output if you use the following command lines in the parameter block:

STAAD PLANE

INPUT WIDTH 79

UNIT METER KN

JOINT COORDINATES

1 0 0 0; 2 0 4 0;

MEMBER INCIDENCES

1 1 2;

DEFINE MATERIAL START

ISOTROPIC STEEL

E 2.05e+008

POISSON 0.3

DENSITY 76.8195

ALPHA 1.2e-005

DAMP 0.03

END DEFINE MATERIAL

MEMBER PROPERTY INDIAN

1 TABLE ST ISHB350

CONSTANTS

MATERIAL STEEL ALL

SUPPORTS

1 2 PINNED

PRINT MEMBER INFORMATION LIST 1

LOAD 1 LOADTYPE Live  TITLE LOAD CASE 1

SELFWEIGHT Y -1 LIST 1

JOINT LOAD

2 FY -10000

PERFORM ANALYSIS

PRINT MEMBER FORCES

PARAMETER 1

CODE INDIAN

NSF 0.85 ALL

KY 1.2 ALL

RATIO 1 ALL

BEAM 0 ALL

TRACK 1 ALL

PERFORM ANALYSIS

CHECK CODE ALL

STEEL TAKE OFF LIST 1

FINISH

Thanks a lot..

The result almost same (1151KN instead of 1047.14KN) when keeping the effective length of the member same. ie 4m, using one end fixed and the other free.

STAAD PLANE

INPUT WIDTH 79

UNIT METER KN

JOINT COORDINATES

1 0 0 0; 2 0 2 0;

MEMBER INCIDENCES

1 1 2;

DEFINE MATERIAL START

ISOTROPIC STEEL

E 2.05e+008

POISSON 0.3

DENSITY 76.8195

ALPHA 1.2e-005

DAMP 0.03

END DEFINE MATERIAL

MEMBER PROPERTY INDIAN

1 TABLE ST ISHB350

CONSTANTS

MATERIAL STEEL ALL

SUPPORTS

1 FIXED

PRINT MEMBER INFORMATION LIST 1

LOAD 1 LOADTYPE Live  TITLE LOAD CASE 1

SELFWEIGHT Y -1 LIST 1

JOINT LOAD

2 FY -1150

PERFORM ANALYSIS

PRINT MEMBER FORCES

PARAMETER 1

CODE INDIAN

NSF 0.85 ALL

KY 1.2 ALL

RATIO 1 ALL

BEAM 0 ALL

TRACK 1 ALL

PERFORM ANALYSIS

CHECK CODE ALL

STEEL TAKE OFF LIST 1

FINISH

Have you checked the column section after executing the design by Staad as to whether the section is same as assigned by you or it has been changed to some higher group? The difference of 1 kn in reaction from the load applied is because of self weight of the column.