8.1 Introduction

Plywood, oriented strand board, waferboard, composite panels, and structural particleboard, collectively referred as wood structural panels, are widely used building materials with a variety of structural and nonstructural applications. Some of the major structural uses include

1. Roof, floor, and wall sheathing

2. Horizontal and vertical (shearwall) diaphragms

3. Structural components

   1. Lumber-and-plywood beams

   2. Stressed-skin panels

   3. Curved panels

   4. Folded plates

   5. Sandwich panels

4. Gusset plates

   1. Trusses

   2. Rigid frame connections

5. Preservative treated wood foundation systems

6. Concrete formwork

Numerous other uses of wood structural panels can be cited, including a large number of industrial, commercial, and architectural applications.

As far as the types of buildings covered in this text are concerned, the first two items in the above list are of primary interest. The relatively high allowable loads and the ease with which panels can be installed have made wood structural panels widely accepted for use in these applications. The other topics listed above are beyond the scope of this text. Information on these and other subjects is available from the APA The Engineered Wood Association.

This chapter will essentially serve as a turning point from the design of the vertical-load-carrying system (beams and columns) to the design of the lateral-force-resisting system (horizontal diaphragms and shearwalls). Wood struc- tural panels provide this transition because it is often used as a structural element in both systems.

In the vertical system, structural panels function as the sheathing material. As such, it directly supports...