HOW DO MULTI-LEVEL STEEL BUILDINGS WORK?
If metal structures could not be more than one tall story, then each major city’s skyline would look drastically different. Not to mention the elevator business would have not made it. It’s because steel is so powerful that today we’ve got these high-rises and skyscrapers.
You may be asking about an existing building, however, and the answer depends, among other things, on the building and the basic design load. Multi-story steel structures have several advantages if you have planned correctly. Let’s look at those advantages and some principles of design to build a multi-story structure or build added floors on an existing one.
DESIGN RULES TO FOLLOW FOR TWO-STORY STEEL BUILDINGS
Typically, the design of a two-story building begins with the initial design of a building, but if the original design is for a single-story building, you can still build it as if more floors will be added in the future. Plan as if you are constructing a multi-story building as you determine the building specifications. Consider the possibility of steel construction expansion at a future date and design a stronger basis and structure when choosing grids and performing preliminary sizing.
Ground circumstances affect the design of a multi-story building significantly. The weight and price of a structural frame per floor area unit rises with height due to the disproportionate increase in wind loading. Due to its lateral stability when used as a constant metal frame, steel is particularly suitable for multi-story building. The continuity of the space between the beams and columns limits the sway of the frame. Another alternative is to construct a braced frame for lateral and torsional load resistance. Vertical bracing transfers horizontal forces to the floor and offers resistance to swaying.
At each level of the story, horizontal bracing braces the horizontal frame through the floor plates and transfers horizontal forces to the vertical bracing planes. In theory, for resistance in both directions and torsion resistance around the vertical axis, at least three vertical bracing frames are needed. Usually, more than three frames are needed for real-world use to provide the suitable quantity of resistance.
The elevated strength-to-weight ratio of steel is another benefit. Building a multi-story constructing with concrete needs highly dense walls to guarantee that the building does not collapse under its own weight. The need for dense walls reduces the quantity of usable square footage within the structure and takes up more room on the construction site.