Structural steel can be economically rolled into a wide variety of shapes and sizes without appreciably changing its physical properties. Usually the most desirable members are those with large moments of inertia in proportion to their areas. The I, T, and C shapes, so commonly used, fall into this class.
- Designation System of Steel Sections
Some examples of this abbreviation system for steel sections are as follows:
1. A W27 × 114 is a W section approximately 27 in. deep weighing 114 b/ft.
2. An S12 × 35 is an S section 12 in. deep weighing 35 lb/ft.
3. An HP12 × 74 is bearing pile section which is approximately 12 in. deep weighing 74lb/ft.
4. A C10 × 30 is a channel section 10 in. deep weighing 30 lb/ft.
5. An MC18 × 58 is a miscellaneous channel 18 in. deep weighing 58 lb/ft, which cannot be classified as a C shape because of its dimensions.
6. An L6 × 6 × ½ is an equal leg angle, each leg being 6 in long and ½ in. thick.