Six Months in Copenhagen

Nothing is more basic to the design and construction industry than a good set of plans. Even as graphics technology facilitates better 3-D renderings, good old two-dimensional plans, sections and details remain an irreplaceable means of conveying information on the construction site.

Even though the project I am working on is in a very early schematic phase, we have started putting together structural plans for the building. My experience is that the best way to anticipate conflicts is just to start sketching. At this early stage in the project we are hoping to see what kinds of challenges will be faced in the final design.  Recall that the project involves decking over an existing highway and rail line and building a 20-story hospital on top of that (Looking for Space, December 5, 2007)

I began by creating a plan drawing for each unique floor, starting at the foundations and moving up 20 stories to the roof.  We made our best educated guess about the shape of the plan; no architect has yet weighed in on the design.  The goal of these drawings was to show all of the major structural components, ie. beams, columns and walls.

There are several conventions available for determining how to draw a plan, and everybody thinks that the way they do it is the one and only correct way. Back home, structural engineers like to show the framing that supports the named floor. Therefore, on the level 2 sheet, you would see the beams and columns supporting level 2. In Denmark the named sheet refers to the framing that you see when you stand on the floor and look up. In this case, on the level 2 sheet, you would see the beams and columns that support level 3. Of course, I drew up the plans my way first, but then I had to redraw everything to match the Danish way.

The next step in creating a set of structural drawings is often to translate the plan drawings into a set of building elevations or sections. These drawings convey additional information about the structure including height between floors and most lateral force resisting members (like steel braces or concrete walls). Usually, we would draw a structural section at every line of columns that contains a unique feature of the lateral system.

The first sections that I worked on sliced through each of the major walls that support the building. After sitting down with my team to review the elevation drawing, we realized several changes that should be made to the structure. In one area, it didn't make any sense to even have a floor. Continuing our meeting, we decided to move most of the walls to create more parking spaces in the garage levels. These are things that we certainly would not have noticed without a detailed set of plans and elevations.

Before doing any calculations, we were able to get a really good feel for the layout of the structure just by sketching out some plans and sections.  Many times a successful project requires a smartly conceived set of plans.