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[subha_mukherjee]

In calculating effective length factor of column as per IS 456 we use      Fig. 27 of IS 456. To calculate beta value we follow SP24 where it is directed to calculate stiffness of beam by 0.5 I/L for braced frame and    1.5 I/L for unbraced frame. All the two cases has been considered for
other end of beam connected to column. Now, if  other end of a beam is connected to another beam,what will be the stiffness of that beam?
Shall we consuder stiffness=0   /  0.75I/L.
                                                             Regards,
                                                                         Subhajit M

[vikram.jeet]

In Manual design Era :
We used to analyse frames using Kani's Method,,
The stiffnesses (I/L ) were taken as under:-

FRAME BEAMS MONOLITHIC TO COLUMNS :-
FOR T BEAMS  -  2.0 I/L
FOR L BEAMS   - 1.5 I/L
For COLUMNS = I /H

HOWEVER FOR BEAMS Monolithic WITH COLUMN AT ONE END AND REST ON ANOTHER BEAM AT OTHER END ( CASE UNDER QUESTION)
IT WAS  O. 75 ( OF ABOVE VALUES) ,,

Factors 2.0 AND 1.5  TAKE OF EFFECT OF SLABS  IN DEFLECTION OF BEAMS AND ASSOCIATED MOMENTS.

ALTHOUGH THESE FACTORS WERE APPROXIMATE, BUT ACTUAL VALUES WERE GIVEN IN TABLE FORM IN CPWD MANUAL VOLUME 1 AND 2 ON MULTISTORIED BUILDINGS,  WHICH WERE EXTENSIVELY USED  DURING THOSE TIMES.

HOWEVER FOR BEAM OR COLUMN WITH HINGE AT ONE END ,,STIFFNESS IS 0.75  DURING THOSE TIMES OF PRACTICE IN ABSENCE OF SOFTWARES.

[atul_123]

Dear Subha Mukharji,

Kindly go through the topic " https://www.sefindia.org/forum/viewtopic.php?p=71201 "

in that you might find some useful data also sharing file share by Mr. N. Prabhakar for your reference.