Wind loads can be automatically are generated in RISA-3D for building models. RISA calculates the ASCE 7 Main Wind-Force Resisting System loads and calculations are based on the Analytical Procedure for Enclosed Rigid Building for All Heights.

Applying wind loads to structures with rigid diaphragms can be done automatically in RISA-3D. In the image below we have a structure that has rigid diaphragms and the wind load has already been applied at each diaphragm level.

Using this method in RISAFloor, we are not actually designing the trusses, but just adding “dummy” bottom and top chords to correctly calculate the loading and help distribute the loads to the walls.

The new 2008 AF&PA Special Design Provisions for Wind and Seismic has now been implemented for wood wall panel design in RISA-3D.

Continuous tiedown systems are used to help resist overturning forces generated by lateral loads, and can be estimated in RISA-3D using the hold-down database and the strap forces.