concrete and steel buiding

[amyrice72]

Is it possible to have 20 plus upper stories of concrete cnstruction transitioning to a platform of steel construction on the lower floors?

 

[larsacious]

Anything is possible. What you are describing though screams soft story from a seismic standpoint.

Why would you/the client want to do this?

 

[slickdeals]

I have seen it done many times the other way round. Concrete podium + steel superstructure.

Agree with larsacious, this is just too heavy a person on really light legs.

 

[msquared48]

This would work well on the other side of the earth though.

Mike McCann
MMC Engineering
Motto: KISS
Motivation: Don't ask

 

[amyrice72]

thanks guys - appreciate the confirmation of my gut. Larsacious- why does a client ever want to do anything - $$$

 

[larsacious]

amyrice72,

I guess I am wondering under what circumstances it would be advantageous to construct a building in this manner. If you elaborate on the condition perhaps some more insight could be provided.

 

[csd72]

If it is for speed of construction then you may want to consider making the lower columns composite as the structure rises thus potentially alleviating the soft storey concerns.

 

[hokie66]

One advantage in using steel for transfer floors is that the deflections due to the upper floors can be calculated to a higher degree of certainty. On the other hand, staged prestressing of concrete floors can compensate for these deflections.