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Hold-down and compression forces are generated and hold-down devices specified at the following locations
There is no force next to a wall segment that is too narrow to resist shear, that is, they have greater than the maximum height-to-width ratio.
Wherever shear walls are offset there is a hold-down at the end of one offset wall and another at the start of the other offset wall
At the corner of a building, separate hold-down forces are generated for the ends of the perpendicular walls, and it is assumed there are separate hold-down devices. Shearwalls does not model the situation where one hold-down is used to carry the force for orthogonal walls meeting at a corner.
Hold-down Force vs. Compression Force
Each hold-down force location corresponds to a compression force location when analyzing for forces in the opposite direction, except that the exact location of the compression force may be offset from the end of the wall slightly less. Refer to Tension vs. Compression Forces for more details .
Vertical Elements
Hold-down and compression forces, but not physical hold-downs, are generated where there is a force location on the level above but no hold-down location on the level below. These forces can be in the interior of shear wall segments, in non-shearwalls, or even where there is no wall on the level below. They are assumed to be carried by vertical elements (built-up wall studs, columns, or posts) to the level below. The vertical elements are shown in elevation view and indicated in the Hold-down Design table, but no hold down devices are input or designed at these locations. Typically, the hold-down will be the same on as the one on the level above at the end of a wall or opening.
If the hold-down on the floor above is above an opening on the floor below but not at the end of the opening, the vertical element ends at the top of the wall and the forces are transferred to both supports of the opening, and combine with hold-down and compression forces at that location on the level below.