People feel uncomfortable in the upper stairs of the tall building when the building move laterally due to wind load or to be accurate the lateral acceleration of the building. Is their any recommendations or limits in code provisions for this acceleration.
Thanks
Khaled, there are several papers available online, that discuss your exact question.
http://global.ctbuh.org/resources/papers/download/2311-wind-induced-motion-of-tall-buildings-designing-for-occupant-comfort.pdf
https://www3.nd.edu/~nathaz/journals/(1999)Mitigation_of_Motion_of_Tall_Buildings_with_Recent_Applications.pdf
Once you have achieved a safe engineering design, assuming the tall structure is to be inhabited by people, you have to address human perceptions. Interesting considerations. Accelerations matter, but also the rate of change of acceleration (jerkiness) and the frequency of the motion. I would expect also, habituation. What makes people uncomfortable at first will probably become less objectionable over time.
Thank you so much Chitaranjan Pany
Could you provide the reference if it is possible?
There are many aspects of this question to consider. Are you considering peak acceleration or rms acceleration? The acceptability guidelines are for a chosen return period. In various parts of the world this varies: 6 months, 1 year, 5 year or 10 year. This choice can depend on wind regime you are concerned about or it may be locally arbitrary. More importantly the acceptability guidance must be frequency dependent, as humans react differently to accelerations at, say, 0.1 Hz than, say, 1 Hz. So, the old guidance in North America, for example, of a ten-year horizontal peak acceleration for a residential building of about 15 to 18 milli-g is a bit simplistic and is not the whole storey (has served structural engineers well, but now most use frequency dependent ISO guidance, or similar). ASCE has a recent publication of this topic and the ATC has just issued an excellent small book in this topic composed by three leaders in tall building design. Suggest you buy that. Cheers, LC.
It depends on the building natural frequency and the return period. You can take the acceptable horizontal acceleration in range 0.02 to 0.2 m/sec2.
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