Drift in Reinforced Concrete Structures - 2nd Time
Drift in Reinforced Concrete Structures - 2nd Time
(OP)
Hay U All again Drifty People,
Thank U for your replies, but again look at this.
As Far as Drift Limits,
UBC97 and IBC2006 codes allow h/100 and h/50 in some cases.
Japanese Code allows h/120.
French code about h/1500.
Fintel h/500.
How did they decide that these are correct limits, and on what Basis?
Thanks Thanks and Thanks.
Thank U for your replies, but again look at this.
As Far as Drift Limits,
UBC97 and IBC2006 codes allow h/100 and h/50 in some cases.
Japanese Code allows h/120.
French code about h/1500.
Fintel h/500.
How did they decide that these are correct limits, and on what Basis?
Thanks Thanks and Thanks.






RE: Drift in Reinforced Concrete Structures - 2nd Time
Seriously, I doubt that the drift parameters you listed are all for the same type structure.
RE: Drift in Reinforced Concrete Structures - 2nd Time
I don't know what was the drift limit imposed on the design of Sears Tower in Chicago, however I do know nobody wants the upper floor spaces due to high drift - people claimed sea-sickness and constant fears. Also, my office was in 10th floor, during windy days, the doors will swing close by itself, the swing of picture frame was clearily visible, not to mention the loud, noisy steel joint was making.
RE: Drift in Reinforced Concrete Structures - 2nd Time
Regarding perception on human comfort, it's not really the drift... it's more on the acceleration or vibration induced by wind.
Ernesto
RE: Drift in Reinforced Concrete Structures - 2nd Time
Would like to agree with your comment, but can you please provide the logic explanation for setting drift limits?
RE: Drift in Reinforced Concrete Structures - 2nd Time
This issue is explained further on some building codes. I've read it before on some british code (i forget the number) or refer to AS/NZS 1170.0:2002 Table C1.
Cheers,
Ernesto
RE: Drift in Reinforced Concrete Structures - 2nd Time
RE: Drift in Reinforced Concrete Structures - 2nd Time
RE: Drift in Reinforced Concrete Structures - 2nd Time
Excerpt from paper presented in link below.
http:
RE: Drift in Reinforced Concrete Structures - 2nd Time
RE: Drift in Reinforced Concrete Structures - 2nd Time
Wind induced drift, swaying, vibration are mainly service criteria. And, the bottom line, serviceability is directly tied to human desire/comfort/perception, which shall be seriously considered in the planning/design stages. The limits on such is highly based on locality, engineering judgement and past experience (studies).
RE: Drift in Reinforced Concrete Structures - 2nd Time
In seismic the deflection criteria is different if you want to compare it with wind multiply the number with your ductility demand factor. H/50 when multiplied by Rw = 8 will give you H/400 which is same as of wind design.
The way ASCE works is that they introduce this Cd factor which is multiplied by elastic forces to obtain in-elastic deformations and then these in-elastic deformations are compared with H/50 limit
RE: Drift in Reinforced Concrete Structures - 2nd Time