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 connections tabulated in the 1986 National Design Specification (NDS). Predicted EYM strengths were compared with 1986 NDS design values to arrive at recommended calibration factors for two- and three-member connections with wood and steel side members loaded parallel and perpendicular to grain over the design space. Design values were changed as a result of basing the bolt-bearing strength of the wood on the specific gravity of a species. Use of Hankinson's formula with bolt-bearing strength was found to be more expedient for loads at an angle to the grain than using the formula with design values for parallel- and perpendicular-to-grain loading. The recommended calibration factors result in some increases and decreases in design values. These factors have been incorporated into te 1991 NDS and a proposed specification for load and resistance factor design (LRFD).