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[paresh_kothari]

Hello SeFIan,
I want a clarification regarding ductile detailing of beam.
As per 13920-2016,

cl. 6.1.1 beams shall preferably  have width to depth ratio of more than 0.3
and
cl. 6.1.3 beams shall not have depth D more than 1/4th of clear span.

So if both the clauses or either one of the clause is not fulfilled then what should be done with those particular beams.

Please reply, drawings are stuck due to this doubt.

Thanks.


Regards,
Paresh Kothari

[sakumar79]

Dear Er Paresh,
     The first clause says "Preferably" and hence is not mandatory. The second clause (which in the old code also used to be "preferable") is now mandatory. Hence, in case of conflict, the second clause would take precedence.

Yours sincerely
Arunkumar

[paresh_kothari]

Dear Arun Kumar,
Thanks for replying.

what should the do if some beams of my structure is deep beam.
Because ductile detailing provision have restriction.

If I will do shear reinforcement design as per 13920 for deep beam, it will give very high value of design shear,
Vu = Va+(Mus+Muh)/L, because L will be very less in deep beam.

[sakumar79]

Dear Er Paresh,
     The code is trying to discourage you from such situations because these deep beams tend to attract more EQ forces locally due to their higher stiffness.

    Sometimes, you have a long span with a very short span next to it. In such a case, depth restriction (L/4) on either span along with the restriction to have uniform beam size for entire span will make it impossible to size the beam. This means you need to replan the structural support system. You can think about moving the short span beam away from the the long span beam (in plan) or the other way around so that the continuity is broken and you can adopt a smaller depth for the shorter span. IMHO Shorter span beam may preferably be away from the column as I feel that the short beam and columns on either side will start to behave like a combined stiff element receiving a huge amount of EQ forces

Yours sincerely
Arunkumar

[prash1730]

Namaste,
In unavoidable circumstances, can we detail the beam as a coupling beam with diagonal reinforcement as done in shear wall?

Best Regards,
PNP