Bolted-connection design

Abstract

Recent failures of bolted connections have raised doubts about our knowledge of their design. Some of the design criteria are based on research conducted more than 50 years ago. This paper compares results found in the literature, using the European Yield Theory as a basis of comparison, to summarize what is known about bolted-connection design and what needs further research. By putting all this information in one place we hope to help engineers and architects design safer timber buildings and structures. In general, the strength is known for a single bolt in a wood side member connection loaded parallel to grain in compression. Less is known for single bolts in tension, loaded perpendicular to grain or having steel side members. The distribution of strength in a multiple-bolt connection is known for up to four bolts in a row. In summarizing the literature we confirm the spacing, end, and edge distance requirements in current multiple-bolt design for Douglas-fir connections. No information exists for distribution of strength or spacing requirements for multiple rows of bolts. The effects of other factors such as fabrication tolerances, duration of load, and preservative or fire treatment are not known. Fabrication tolerances appear to have a large effect on connection strength, but this effect has not been quantified.

A Comparison Between the EN 383 and ASTM D5764 Test Methods for Dowel‐Bearing Strength Assessment of Wood: Experimental and Numerical Investigations

“…Traditionally, dowel‐type wood connections have been modelled based on Johansen’s model [2], proposed in 1945, which has been incorporated in design codes [3, 4]. Johansen proposed a beam (dowel) on foundation (wood) model based on maintaining equilibrium normal to the dowel and balancing internal and external moments.…”

Bolts, Drift Bolts, and Pins

“…McLain and Thangjitham (1983) examined this theory for bolted wood connections loaded parallel-to-grain and found good agreement between predicted and observed values. Soltis and others (Soltis et al 1986iSoitis andWilkinson 1987) found agreement between predicted and observed values for paralleland perpendicular-ta-grain loading.…”

LRFD for Engineered Wood Structures—Connection Behavioral Equations

“…Similar equations are developed for other connection geometries. The development of the equations is well documented by Soltis et al (1986Soltis et al ( , 1987, McLain and Thangjitham (1983), and Patton-Mallory (1989) for bolted connections and by Aune and Patton-Mallory (1986a, 1986b for nailed joints.…”

“…assuming that members and fas teners behave as ideal rigid-plastic materials. Numerous researchers have published verification of EYM for several connection types (Soltis et al 1986(Soltis et al , 1987McLain and Thangjitham 1983;Whale and Smith 1986). A typical example of predictive ability is seen in Fig.…”