Structural Framing Systems

Some characteristics of my structural framing system:

• I started with placing grid lines near the inside face of exterior walls and I placed one grid line per each exterior wall. Then I added more grid lines to have roughly 30’ between the lines.
• I placed columns at the grid intersections. Before that, I adjusted the position of some grid lines to avoid placing columns in inconvenient places inside that could block circulation. For example, I aligned one of the vertical grid lines with the right edge of the atrium.
• I chose steel columns (W10X49) and I decided to keep them exposed at several places. I did not add walls around them, but some of the columns are partially hidden by the walls. These columns don’t take up too much space and my building has a lot of open space so having some exposed columns is not an issue, and I liked the aesthetics of it.
• One column is outside the building, in the patio area. It just happened like that due to grid intersections, and I didn’t want to change my structural design to force this column inside. I also thought it would be nice to have some exposed structural elements on the outside as well.
• Columns on the first floor have a -6’ offset that goes into the ground and ends with isolated column foundations.
• The column layout is the same on both floors. I designed my spaces with that thought from the very beginning as I didn’t want to have complex structural systems.
• For beams I used W12X26 steel beams. I first placed major beams connecting the columns, and I then added beam systems between them. I used fixed number layout for beam systems. There are several beam systems of different sizes. The reason is that I had to organize the beams around floor openings (atrium, elevator/mechanical room shaft, and staircase). I tried to make sure most of the floor is supported by beams.
• Beam layout is the same on both floors.
• There are several structural walls: the ones around elevator/mechanical room shaft and staircase. These are basic generic 8” walls.
• Floors on levels 1-3 are also structural: 3” LW concrete on 2” metal deck.
• All the beams have a -5” offset to ensure the steel beams are below structural floors.

Some issues/challenges:

• Clash detection tools showed a lot of clashes, but a vast majority of them were modeling inaccuracies. Some of them were valid clashes, for example columns going through floors.
• I have a few columns that are within interior spaces but they are close to the walls and are in a relatively large spaces so they are not blocking circulation. But later I realized there is one column in a smaller room on the second floor whose location is not ideal. But I left it there as I didn’t want to change my structural system too much so late in the process. This is also planned to be a copy room so it’s not a big aesthetic issue if there is a column in there.
• There are two beams that are sticking out of the walls on the outside (in the patio area) and it was an intentional choice, but I realized they would be clashing with glass panels. I’m not familiar with exactly how this would work, but I assumed there is a way to make the glass panel go around the beam, so I left it like that in my model.