Simple wind pressure loading
The simple wind load method can be used as an alternative to the wind wizard, either where this may not be available or appropriate for certain geographical locations/ country codes, or where the engineer considers it is more detailed than necessary for the stage of design and/ or overall building load considerations.
- Apply to Diaphragms
- Apply to Wall/ Roof Panels & Open Structure Members
Apply to Diaphragms
When using this option, the simple wind load is decomposed as point loads on to any rigid diaphragms between the top and bottom level of the simple wind load. Wall and roof panels are ignored.
When the option to apply to diaphragms is enabled the following further option is provided to control the application of the wind load:
Ignore diaphragms on lowest level - If for some reason there are diaphragms at the ground level, then you may decide to check this option in order to ensure no load is lost directly to the foundations.
Apply to Wall/Roof Panels & Open Structure Members
- Wall and roof panels have area loads applied which are then decomposed on to the structure members.
- Open structure items (i.e. those members, ancillaries and equipment entities for which the “Apply open structure wind load” property has been enabled) have loads applied directly.
For wall and roof panels the load application is broadly similar to that of the wind wizard, with the following notable differences:
Load is applied only to the windward outer surface of wall and roof panels - not leeward or those parallel to the load direction.
The applied area load direction is essentially that of the Simple wind, not Normal to panel surfaces.
For wall panels, loads are decomposed as member loads for panels set to Decompose to Nodes, as well as when set to decompose to Members (the decompose to Diaphragms option is followed).
When the option to apply to wall/ roof panels & open structure members is enabled there are the following further options to control the application and extent of the wind load:
Pressure > At highest point of item/ Average between highest and lowest point - the operation of these options briefly is as follows:
At highest point of item -wall/roof panels & open structure members are loaded using the pressure at the top of the item. (Click here for an illustration).
Average between highest and lowest point - wall/roof panels & open structure members are loaded using the average pressure between the top and bottom of the item. (Click here for an illustration).
Extend wind to top of building - when enabled, wall/roof panels & open structure members receive the wind load, irrespective of whether they lie within, or outside the load height. Otherwise only those wall/roof panels & open structure members that lie within the load height receive load. (Click here for an illustration.)
Extend wind over full building width - when enabled, wall/roof panels & open structure members see the wind load, irrespective of whether they lie within, or outside the load height. Otherwise only those wall/roof panels & open structure members that lie within the load width receive load. (Click here for an illustration.)