Behavior of end-plate moment connections with bolts in the extended portion

Abstract

An investigation using analytical and finite element analysis techniques has been conducted to study the behavior of extended end-plate moment connections having bolts exclusively in the extended portions of the end-plate. The objective of the study is the determination of the appropriate end-plate thickness and bolt diameter for a particular design moment. Finite element method has been employed to study the behavior of end-plate connections of several universal beam sections. The moment-rotation relationship of the connection has been singled out as the best characterization of connection behavior. The finite element analysis techniques used have been validated against previous full-scale experimental results of conventional end-plate connections having both inner and outer bolts. In absence of any available experimental data on end-plate connections with only outer bolts, the finite element analysis has been considered as a substitute to full-scale experiments. The contribution of the endplate and the bolts to the overall connection behavior has been investigated over the full range of loading. An analytical formulation to determine the required end-plate thickness for the extended end-plate connection for a particular design moment has been developed from plastic theories of structure. The results from the analytical formulation have been compared against those from the finite element analysis. Excellent agreement has been observed at design moments near the plastic moment capacity of the connecting beam. In view of the deviation of results at lower moment values the analytical formulation has been modified with a multiplication factor. The modified analytical formulation gives excellent agreement over a wide range of design moments. Connection configurations of this type lead to greater flexibility as the connection behavior is dominated by the bending of the end-plate. In view of the excellent agreement of the proposed analytical formulation and finite element analysis results, the proposed formulas for determining end-plate thickness and bolt diameters can be said to be satisfactory for application in design of the particular connection configuration of the present study.