Elevator shear core with doors on opposite sites

[hnguyen8]

Hi everyone,

Does anyone have any experience with elevator shear cores with openings on opposite sites on adjacent floors? I've drawn a little sketch attached to illustrate. Seismic load is the main concern. I'm thinking the continuous flanges can be designed to take out flexure and the floor diaphragms can be designed to transfer shear from the "web" of the wall into the floor diaphragm then back out to the wall "web" on the other side.

All comments are appreciated!

 

[KootK]

and the floor diaphragms can be designed to transfer shear from the "web" of the wall into the floor diaphragm then back out to the wall "web" on the other side.

I'd agree with that. With conventional construction techniques, you're often sort of transferring wall shears out into the slab and back at every floor level anyhow. Might be prudent to have lengthy drag strut rebar groups in the left-right direction over the left-right shaft walls.

I like to debate structural engineering theory -- a lot. If I challenge you on something, know that I'm doing so because I respect your opinion enough to either change it or adopt it.

 

[Akeee]

I had one of those on a 5th story building, seismic area, pga 0.30g.
This will give you some headache but depends a lot on the walls distribution on the building floor.
It's the main core ? What percentage of total floor shear is distributed to this elevator shaft ?

 

[Akeee]

Btw you draw the earthquake arrow from left to right, what happens from down to top?

 

[hnguyen8]

Thank you KootK and Aketr for your help!

@Aketr: The other direction is also part of the seismic design, but less of a problem because the side walls are continuous from top to bottm.

Thanks!

 

[Akeee]

I didnt do anything, but your welcome.
If you have more questions when doing the design please feel free to ask them.
Be carefull on the compressive concrete strut check

 

[LECT12]

You need to design a coupling beam at the wall openings to transfer forces to the "flanges". Having the openings will reduce the stiffness of your wall since you will have reduced composite action between the flanges. The coupling beam needs to be designed for combined axial, shear, and bending. If you have low floor-to-floor heights your beam may be shallow. If you're in a high seismic risk area you will have to use specially detailed coupling beams.