Yield Line Analysis of Bolted Hanging Connections

Abstract

The beam-to-girder connection made by fastening the top flange of a beam to the bottom flange of a transverse girder with bolts acting in tension is an example of a bolted hanging connection. Connections of this type are not often used for the support of primary members. When their use is unavoidable, their allowable load is estimated by a rough analysis and they are detailed very conservatively. It is desirable to rationalize a simple analysis, practical for general office use, so that the designer may be at ease with an economical solution when the use of bolted hanging connections is required. The bolted hanging connection can be more useful to the designer if a practical design procedure is available. Yield line analysis provides a solution, with due regard for superimposed longitudinal member stresses, for the most commonly encountered cases. Limitations are placed on the edge distance and on the proximity of bolt to web. The effect of prying force on fasteners is determined by accepted empirical formulas. Fasteners in long members are evaluated by analogy to the conventional (short member) case.