Parametric analyses on the initial stiffness of flush end-plate splice connections using FEM

Existing design procedures for steel frames have been modified during the last three decades to incorporate the semi-rigid behavior of the connections into the frame design advancement. Knowledge in initial rotational stiffness of a connection is important for the global elastic analysis of frame structures. This paper presents the results of several parametric analyses on the Initial Rotational Stiffness (IRS or Sini) of Bolted Flush End-plate Beam (BFEB) splice connections using Finite Element Modeling (FEM). The FEMs have taken into account material behavior, geometrical discontinuities and large displacements. The analyses have been calibrated to experimental results that are also briefly reviewed in this paper. These models clearly support the numerical results and show accurate correlation between FEM and experimental results of the connections behavior. Due to the multitude of influencing parameters, an analytical description of the BFEB connections behavior has been delivered. This is based on component method, which is proposed by the Eurocode 3 as the equivalent T-stub. Also comparisons between numerical and analytical data for initial slop of moment–rotation curves are accomplished. The method for accuracy in predicting values regarding the Sini of BFEB connection is also discussed.