Collector Force Location

Drag Strut Forces

In general, drag strut forces are evaluated and shown at the sides of any full-height sheathing segments that do not meet the perimeter of the building. These locations are where the local maxima and minima of tension and compression forces occur, and the axial forces vary linearly between these points.

Specifically, drag strut forces are evaluated:

• Where the side of an opening meets a full-height segment within a shear wall
• At end of the last shear wall in a shear line if it does not tie directly into perimeter walls.
• Where there is a gap between the end of one shear wall and the start of the next one.
• Across non-shear walls in a shear line
• Across shear walls in a shear line that receive no force due to low stiffness in the procedure to equalise deflections.
• At the transition in the plan of an irregular structure, such as an L-shaped house.

Vertically, drag struts are typically located at the top of the wall, and can be incorporated into the top plate of the wall over openings, diaphragm chord, or beam connecting two walls. In Elevation view, they are shown just below the top of the wall.

Force-transfer Straps and Blocking

The forces in the elements used to transfer forces around openings in force transfer walls are calculated at the sides of the openings, where the forces are at a maximum. They are therefore at the same location in plan as some, but not all, of the drag strut force locations.

Vertically these elements are placed immediately above and below openings.