Hold down (structural engineering)

A hold down resisting uplift from a timber shear wall

Holdown (hold-down, hold down) or tie-down in structural engineering refers to the steel device or hardware that is installed at the end of a plywood shear wall. The holdowns provide uplift resistance against the overturning moment imposed on the wall due to "in-plane" lateral load applied at the top of the wall. A hold-down may also refer to clamping device used to anchor a pipe to a structural steel element or concrete floor or allow movement of the pipe in an axial direction.^[1]

At the bottom, the holdown is connected to the concrete foundation or structural slab by an embedded or epoxied anchor bolt. At the top, the holdown is connected to a wood post with screws, nails or bolts.

Hold Down Clamp for Anchoring Pipes

References

1. Hold-Down Pipe Clamps Piping Technology and Products, (retrieved May 2012)