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Basic Shear Wall Diagram

This second example is for a wall with higher shear loading that begins to overtake the weight of the system.

Resulting Forces

Note that as lateral loads increase, the maximum tension and
compression in the triangular force pair increases.
At the bottom diagram, adding the two resulting forces together
yields a diagram that indicates a residual tension in the system.
Providing all other criteria are met, this tension can be left
unaddressed (no hold-down).

For lateral loads (triangular force pair)...

Mot = (Vroof * H) + (Vwall * H/2)

For vertical loads (rectangular force)...

Mr = (Total Weight * L/2)

And finally...

"a" = (Mr-Mot)/(Total Weight)
max. comp. = (2/3)*(Total Weight/a)

Alternate Result

The bottom diagram can be redrawn to show a single force in place of the triangular distribution. This is the first step in understanding the use of hold-downs in shear walls.

Resulting Forces

Note that as lateral loads increase, the maximum tension and compression in the triangular force pair increases. At the bottom diagram, adding the two resulting forces together yields a diagram that indicates a residual tension in the system. Providing all other criteria are met, this tension can be left unaddressed (no hold-down).