Designing vertical bracing connections

Transcript

Designing vertical bracing connections in ILX Connection. We will design a brace gusset at a beam-to-column joint, then take a short look at truss connections.

Start a bracing gusset

Open the New connection wizard, and pick the vertical bracing gusset in the Truss and bracing group. ILX Connection shares the brace force between the gusset edges and the beam-to-column connection with the uniform force method.

Loads and framing

Enter the brace force, the beam end reaction, and the axial transfer force in the beam. Tick Brace force reverses to check the brace in both tension and compression. Then pick the beam and the column, and whether the gusset sits on the column flange or the column web.

The brace

In the Brace section, choose the shape: double angles, a single angle, a tee, a slotted rectangular or round HSS, or a W shape. Set the bevel as a rise and a run, then lay out the bolts or the welds. Our example is a double-angle brace, bolted to the gusset.

W-shape braces

For a W-shape brace, the web lies in the plane of the gusset. Splice the web with two tees, or bolt plates to the flanges and slot them over the gusset. ILX Connection checks the brace, the tees or plates, the bolts, and the gusset.

Gusset and uniform force method

In Gusset and UFM, set the plate thickness. The gusset size can be found for you, so that the edges carry no moment. The key results show the forces on each edge. The drawing shows the work lines, the work point, and the Whitmore section.

Gusset edges

The gusset is welded to the beam flange, or bolted to a tab plate that is welded to the beam. At the column, weld it, or bolt it with an end plate, two clip angles, or a single plate. Here we pick an end plate, and its bolts and welds are checked right away.

Beam-to-column connection

The beam-to-column connection can be designed here too. Choose double angles, a single plate, or a shear end plate. It is designed for the beam reaction plus the gusset forces, in shear and in tension.

Checks

Every check is listed in plain language: the brace and its bolts, block shear, Whitmore yielding and buckling, the gusset edges and their welds, and the beam and column webs.

Seismic mode

For a special concentrically braced frame, set Seismic design to SCBF. The brace force is replaced by the expected strengths of the brace, in tension, in compression, and after buckling. ILX Connection also checks the gusset hinge zone, and can add net-section reinforcing plates and a beam splice that releases moment. In this example, every check passes except the hinge zone. Its message tells you how far to move the brace end out, or you can make the gusset smaller.

Truss connections

For trusses, use the Truss connection type. It designs a support joint, where a tee chord and a gusset are bolted to a column with clip angles. It also designs a panel point, where the web members weld to the chord stem. Start from one of the published examples, then change it to suit your truss.

To learn more, open the user manual from the help button in any section. Try it at ilxconnection.com, or write to us at support@ilxstudio.com. ILX Studio, LLC is not affiliated with AISC.