SMF Beam-Column Connection

References

Seismic Design Manual

Details

The SMF beam-column connection design presented in this example has been chosen to demonstrate the application of the design provisions for prequalified RBS connections in accordance with ANSI/AISC 358. This example demonstrates that the RBS geometry developed below is satisfactory. Some of the results from this example are used in Example 4.3.3. The geometry of an RBS connection is not unique and alternative configurations of the RBS geometry are possible.

Refer to Joint JT-1 in Figure 4-8 of the reference. Design the connection between Beam BM-1 and Column CL-1 using the reduced beam section (RBS) shown in Figure 4-9 of the reference. All beams and columns are ASTM A992 W-shapes. Plate material is ASTM A572 Grade 50. The gravity loads on the beam are:
  • wD = 0.84 kip/ft
  • wL = 0.60 kip/ft

Refer to the figure in the reference for additional details.

Calculations

Calculations

VD = 30 ft × 0.94 kip/ft = 25.2 kips
VL = 30 ft × 0.60 kip/ft = 18 kips

Results

Table 1. Comparison with AISC Seismic Design Example 4.3.4
Parameter RAM Connection Reference Difference
Mpr (kip·in) 8,655 8,670 < 1%
Vp (kips) 72.1 72.1 none
Mf (kip·in) 9,700 9,720 < 1%
Plastic moment of hte beam based on the expected yield stress (kip·in) 11,000 11,000 none
Shear strength of the panel zone (kips) 480 480 none

Input

The following data is input into the New Joint dialog:

Joint Data tab:
  • Joint = BCF
  • Beam/Section = W 24x76
  • Beam/Material = ASTM A992 Gr50
  • Column/Section = W 114x176
  • Column/Material = ASTM A992 Gr50
  • Seismic load resisting system = OMF (set
The following data can be added after the Seismic Parameters option is set in the Connection Design Configuration dialog:
  • Seismic load resisting system = SMF
  • Beam/ Length, L = 30 ft.
  • Beam / Seismic Design / RBS Connection = Yes
  • Beam / Seismic Design / Horizontal distance to start of RBS cut, a = 5.5 in.
  • Beam / Seismic Design / Length of RBS cut, b = 18 in.
  • Beam / Seismic Design / RBS cut maximum depth, c = 2 in.
  • Beam / Seismic Design / Shear due to gravity loads between plastic hinges, Vg = 17.25 kips
Loads tab:
  • V2 (beam) DL = 25.2 kips
  • V2 (beam) LL = 18 kips

Select the Smart Connections/Smart DW connection type.

The following data is input into the Connection Pad:

General Information group:
  • Design criteria / Frame stability considered in analysis = checked (set the option)
Stiffeners / Transverse Stiffeners group:
  • Position = both
  • Full depth = checked (set the option)
  • Transverse stiffeners width, bs = 5.5 in.
  • Corner clip length, cc = 1 in.
  • Corner clip width, cc = 1 in.
  • Transverse stiffener thickness, ts = 0.75 in.
  • Material = A572 Gr 50
  • Welding electrode to support = E70XX
  • Weld size to support (1/16s in), D = 8
Stiffeners / Column Web Panel Zone Stiffeners group:
  • Stiffener type = doubler plate
  • Position = one side
  • Stiffener thickness, ts = 0.50 in.
  • Material = A572 Gr 50
  • Weld type to column flange = fillet
  • Welding electrode to support = E70XX
  • Weld size to support (1/16s in), D = 3