Beam supporting column

[tclat]

Hi

Is there any special consideration that needs to be given to a r/c beam supporting a r/c column particularly regarding lateral retraint?

I've done the simple checks (shear, monemt and deflection) The r/c beam will be cast monlithically with a 6" r/c floor slab so I presume the beam will be braced laterally. Any concerns here?

Thanks

 

[kbbandw]

yes the beam will be braced laterally as long as the floor slab diaphragm itself is laterally supported by a lateral load resisting system such as a shear wall or frame. Do you have large openings in floor slab in the vicinity of this beam?

 

[csd72]

A beam that supports a column is normally called a transfer beam.

Be careful of the deflection in this beam as it will effect the moment distribution

 

[NS4U]

Why do you think you would need to consider lateral stabilty just becuase this is a transfer beam? I am confused.

What if it was a normal beam with a giant load in the middle? You still concerned about lateral stability?

 

[sfat]

As KBbandw said,you have to have a lateral force resisting frame and then its ok if that frame is designed according to lateral forces.
Transfer beam is critical,and columns supporting this beams become more critical when you talking about zone 3.seismic forces have to be doubled to check shear in such case,as code says.coulmn ties detail also needs attention.
check chapter 21 ACI code,special provisions for seismic design.
Even in zone 2,you need to satisfy shear+torsion criteria in beam,as well as check supporting columns for stability also.
it would be more convinient if you tell us the data like,seismic zone,building height,and the no. of floor the picked-up column has to support are.

 

[bazflexure]

What tupec connection u have provided for the column at the base.Fixed or Hinged.

I think this type of loading transfer mechanism will create complex stress in beam during strong Earthquake.

 

[frv]

Also, since a column will introduce a large load at the top of the beam, if the span of the transfer girder is relatively small, you may not be able to design the beam with traditional beam theory. Make sure you don't have to design this beam using the strut and tie model. (usually only applicable if L/d is<=4)

 

[kslee1000]

Watch out reverse (double) curvature of slab on each side of beam, consideration shall be given to continuity of reinforcing within column strip.