Overall wind drift check

Tekla Structural Designer
Tekla Structural Designer

Overall wind drift check

When activated, by default this check considers all columns (of all materials), and all walls at every level in the model.

In this check the overall wind drift ratio, (H / Δmax) is compared against a user defined limit.

For levels set as floors a Reporting Level option is displayed in Level Properties. This is used in the above calculation as follows:




Distance between the highest and lowest levels with Check for drift selected.



Maximum lateral deflection at the highest level with Check for drift selected.

By default the Δmax is calculated in the resultant wind drift direction only:

Δmax = Δmax,Resultant

By unselecting Check for Resultant Wind Drift in Design Settings it is calculated as follows:

Δmax = max [Δmax, Dir1, Δmax, Dir2]

A workflow for running the check is outlined below:

Configure the check and set the limit

The check is activated from Design Settings.

On the Drift Checks page (if working to the ACI/AISC head code) or Sway & Drift Checks page (if working to any other head code), select Check for Overall Wind Drift and then enter the limit required.

Note: By default the check is activated for new models with the limit set as 500.

By default the check is performed in the resultant wind drift direction only, but by unselecting Check for Resultant Wind Drift it can be performed in each of Building Directions 1 & 2 if required.

By default the check only considers the effects of the wind loadcase(s) in wind combinations, but by unselecting Check wind cases only it will consider the effects of all loadcases in wind combinations (which would include drift induced by gravity loads).

Run the check

Provided the check has been activated, wind load combinations are automatically checked for overall wind drift during the structure static design, and also when any 3D analysis is run in isolation. If a sub-set of combinations are considered for analysis then only those combinations are checked, (allowing engineers working on larger structures to investigate and optimize the lateral load resisting systems more rapidly).

In performing the checks, the maximum lateral deflection (Δmax) associated with the highest level of active check for drift is determined for each combination using the combination SLS (Service Level) factors - (which can be < 1.0). The ratio of H / Δmax is then compared against a user-defined limit.

Review the check status and details

Once the check has been run, an Overall Wind Drift status is reported in the Design branch of the Status Tree. Beneath the status the node with maximum wind drift deflection value and its associated combination are listed.

Right clicking on the value opens a context menu, from which you can choose Highlight Node to see where the maximum occurs in a solver view.

You can also choose Details... to open a dialog which shows the results of the check.

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