New esclator connection with existing concrete beam

[ali07]

Hi Guys,

I have a situation where client need to install second escalator beside existing. I need to know how the connection works. Beam is 60ft span and i don't know whether it has to chip for some distance or not to make top flush with floor finishes. Any practical guidance is appreciated. Thanks

 

[JAE]

Can the existing beam support the added load?

 

[MiketheEngineer]

Check with the manufacturer??

And good question - can the beam carry the extra load. They weigh a lot and carry a lot of people..

 

[ali07]

Beam can support extra weight. How the detail workout to support. In steel structure it might be easy, but with existing situation what would be the supporting arrangement.

 

[youngstructural]

IF there is no additional reinforcement necessary to carry the added load (which actually surprises me quite a bit), and the only problem remaining is how to make the connection, I would suggest you refer to the Hilti Fastening Technology Manual. It has a similar problem solved in detail at the back in section 5 "Bonded-In Reinforcement". I'm looking at the 2005 International issue.

Regards,

YS

B.Eng (Carleton)
Working in New Zealand, thinking of my snow covered home...

 

[ali07]

Actually escalator is planned to be placed at the edge of the beam that's why stresses are not increases much.

 

[youngstructural]

The fact that it's at the edge of the beam should not reduce your stress... The point of application along your beam will dictate the stresses in your beam. The fact that it is on the edge of your beam might actually INCREASE your stresses by addition a torsional load case!

Be careful, and be certain that your beam can take the loads.

Cheers,

YS

B.Eng (Carleton)
Working in New Zealand, thinking of my snow covered home...

 

[ali07]

I think here torsion is not a problem. It is balancing with a 28ft span on the otherside. If you apply load close to support of beam, it have a slight increased stresses. Application of load is not at the center of the beam.

 

[csd72]

Ali07,

I agree that the slab span on the opposite side should be sufficient to take out the torsion.

As others have stated, you need to get the manufacturers standard connection details so that you can design this.

 

[youngstructural]

Given a 28ft dead load return span on the opposite side, I would also agree that you should not have a torsion problem. And since you are away from your centre span, that would explain why your beam is still able to carry the loads...

That said, have you chased your load path? I would assume that since you are loading a beam towards one end most of the load from the escallator is going to go down one column and thus increase the load on the footing.

Also, you might want to think about a scabble face and surface saturated dry condition when you do make your connection.

Keep up updated, this is an interesing one. I would also be very interested in seeing your final detail.

Regards,

YS

B.Eng (Carleton)
Working in New Zealand, thinking of my snow covered home...

 

[ali07]

Thanks for your interest. Actually i was much interested in fastening detail of escalator. There is much relief to the beam due to the fact that one concrete stair spanning 40 ft having weight of about 40,000 lbs at centre being removed and i am adding 40,000 lbs at the edge of beam. I think there should be no question of stresses. I am actually expecting the connection detail for this without cutting the beam to install escalator support.