A shear wall is a stiff vertical wall, usually reinforced concrete or masonry, that resists sideways forces from wind and earthquakes and carries them down to the foundation.
Each floor collects lateral force and, acting as a diaphragm, delivers it to the walls. The walls take that force as in-plane shear and resist the overturning it creates at their base. Shear walls are one of the main lateral systems in parking structures; the other common one is moment frames.
Where garages put them
- Around stair and elevator cores, where solid walls are needed anyway.
- At the ends of the building or along a party line, where views and openings matter less.
- In precast garages, as precast wall panels connected to the floors, where the connections are as important as the walls. See precast concrete.
What they cost
- Openness. Solid walls count against the openings an open garage needs for natural ventilation. See openness calculation.
- Sightlines. Long blank walls reduce visibility and natural surveillance. See CPTED.
- Flexibility. Walls are hard to move later, which matters if a garage may be converted. See future-flexible design.
The Parkonomics view
A shear wall does its best work where a garage wants a solid wall anyway. Put the lateral system at the cores and the ends, and the parking floors can stay open, bright and easy to see across.
Related terms: Lateral Loads, Seismic Loads, Wind Loads, Floor Diaphragm, Moment Frames, Openness Calculation