IMPORTANCE OF BASE CONNECTIONS

1.     IMPORTANCE OF BASE CONNECTIONS:-

Column base connections are one of the most important components in steel structures because they transmit forces from the entire structure into its foundation. An exposed column base plate connection is an assemblage of a column, plate, grout pad, concrete pedestal, anchor rods, washers, and nuts, used to attach a column to its concrete foundation (shown in Figure 1). The plate is welded to the bottom of the column and anchor rods are driven through the thickness of the steel plate and grout pad, and into the concrete foundation. The connection must be capable of resisting shear and axial loads, as well as bending moments. Exposed column base connections have performed poorly in previous major earthquakes in the United States and Japan (Grauvilardell et al., 2005), signaling that although the qualitative response of these connections is well understood, quantitative characterization of this response is not well-established, and relies on sparse experimental data (Fahmy et al., 2000).