Comfort Accelerations limits for Tall Building

[blihp]

i am starting on the design of a number of tall buildings, ranging in heights from 25-50 storeys and am aware that i need to design the stability systems to ensure that accelerations from wind are kept to allowable limits.

I have a few questions on this:

1/ where can i find some stated limits, preferably from codes, on what acceptable accelerations are and for what return period. I have read and heard people discuss values like 12-15 mg for residential buildings, 18-20 for offices, but i would like to see some solid evidence of these limits

2/ are there any limits on rotational movement, ie when a floor plate twists torsionally on plan from wind.

3/ how can i calculate accelerations, particularly at the concept stages of design, before a wind tunnel test is carried out

many thanks in advance

 

[seattlemike]

Accelerations due to wind need to be kept under 1% of g.
See Simiu and Scanlan's "Wind Effects on Structures"
But if you glance at the calculations on Table 9.1.5 you will see that they are quite heinous.