Alternative wind load decomposition method for complex models

For complex models the placement of wind walls required by the Wind model method can be a time consuming operation.

In such a situation (provided the model has suitable rigid diaphragms), the following alternative offers a quicker and simpler way to apply approximate wind loads:

Use engineering judgment to clothe the structure with an arrangement of simplified wind wall panels around its bounding box,
set the wind walls to decompose to rigid diaphragms,
proceed with the Wind model method

Simplified wind wall panels example

In theory, because wind walls set to Decompose to Rigid Diaphragms don't have to physically connect to the diaphragms, even a very complex model could be clothed with just four simplified wind walls defined along its bounding box, as illustrated below:

Figure 1. Complex model prior to placement of wind walls

Figure 2. Simplified wind walls placed around the "bounding box"

Figure 3. Simplified zone loads after running the wind wizard

Figure 4. Resulting point loads on rigid diaphragms after decomposition

Such an approach could be used to rapidly establish approximate wind loads (based on the rectangular building envelope) which could then be refined at a later stage if necessary.

Note: If this method is adopted you are strongly advised to review the wind zones that are formed, and the resulting decomposed loads to ensure they meet your expectations - it will not give good results for all models.

If the decomposed loads produced by the above approach are not satisfactory, you might decide to take greater control by applying the loads manually.