Joint Details in Post and Beam Framing

Abstract

Although most wood design is now undertaken by firms specializing in this work, nonspecialists have occasion to design in wood from time to time. As with other structural materials, even a simple understanding of the characteristics of the material will enable designers to avoid many subsequent problems. The intent here is to present several relatively simple examples. Although nails may be the most commonly used connectors, bolts and lag screws tend to be used when member thickness increases from 38 to 89 mm ~1 1 2 to 3 1 2 in.!. With wood, the ideal connector when members overlap would be a device that develops shear over the entire contact face. Although this is a characteristic of adhesives, their use on-site is problematic. The development of the lightweight galvanized truss plate has revolutionized fabrication of house roof trusses by eliminating the lap joint, yet providing distributed shear connections. Similarly, the glulam rivet or nail with appropriate nail plates 4.8 to 6.4 mm ~3/16 to 1 4 in.! in thickness, has provided distributed shear connections for larger members. Concurrently with the development of the truss plate and glulam rivet, the Swiss are believed to have developed the equivalent of a two-sided truss plate that could be inserted between the contact faces of lap joints. As with truss plates, presses were needed