BOLTED CONNECTION DESIGN VALUES BASED ON EUROPEAN YIELD MODEL

This paper discusses the calibration of connection strengths predicted by the European yield model (EYM) to the design values for bolted con nections tabulated in the 1986 National Design Specification (NDS). Pr edicted EYM strengths were compared with 1986 NDS design values to arr ive at recommended calibration factors for two- and three-member conne ctions with wood and steel side members loaded parallel and perpendicu lar to grain over the design space. Design values were changed as a re sult of basing the bolt-bearing strength of the wood on the specific g ravity of a species. Use of Hankinson's formula with bolt-bearing stre ngth was found to be more expedient for loads at an angle to the grain than using the formula with design values for parallel- and perpendic ular-to-grain loading. The recommended calibration factors result in s ome increases and decreases in design values. These factors have been incorporated into te 1991 NDS and a proposed specification for load an d resistance factor design (LRFD).