Steel Design Practices (and examples)
Fig. 1: An Example of Steel Construction (L.V. City Center)
From Wikipedia, "Steel is a metal alloy whose major component is iron, with carbon being the primary alloying material." Carbon acts as a binding agent, locking the otherwise easily-moved iron atoms into a rigid matrix. Varying the amount of carbon and its distribution in the alloy controls the qualities of the resulting steel. With the increased carbon, steel is harder and has a much higher tensile strength than iron, but is also more brittle (hardness and ductility can also be altered). One classical definition is that steels are iron-carbon alloys with up to 2.1 percent carbon.
The American Institute of Steel Construction (AISC) provides the design criteria for most steel elements. The most common Design Code currently being used by the IBC is the AISC 360 (13th edition).
The different types of steel:
- Carbon steel (the most common type for design purposes
- Damascus steel, which was famous in ancient times for its flexibility, was created from a number of different materials (some only in traces), essentially a complicated alloy with iron as main component.
- Stainless steels and surgical stainless steels contain a minimum of 10.5% chromium, often combined with nickel, and resist corrosion (rust). Some stainless steels are non-magnetic.
- Tool Steels
- HSLA Steel (High Strength, Low Alloy)
- Alloy steels (e.g. ferrous superalloys)
Common Steel Properties :
Common Steel Properties include (english units):
- E =28,000-30,000 ksi (commonly 29,000 ksi is used)
- Poisson's ratio (v) = 0.25-0.30 (commonly 0.29-0.30 is used)
- Thermal deformation = 6.5x10-6 1/ºF
- γ = weight density = 490 pcf
- ρ = mass density = 15.2 slugs/ft3
Common Steel Properties include (metric units):
- E =190-210 GPa
- Poisson's ratio (v) = 0.27-.30
- Thermal deformation = 11.7x10-6 1/ºC
- γ = weight density = 77 kN/m3
- ρ = mass density = 7,850 kg/m3
- Gere, James M. "Mechanics of Materials, Sixth Edition",2004