Structural steel design is a branch of Structural Engineering that focuses on the design of steel structures where the structural steel is used as a construction material in a variety of shapes, each having their own properties.
Pros and Cons of Structural Steel
Can be used to design high-rise buildings (skyscrapers)
Has a good tensile and compressive strength (equally)
Is a ductile material, and is, therefore, strong enough to withstand external pressures (earthquake, wind, etc.)
Is a recyclable material and the recycled material can be used for the construction of a new structure (has good scrap value)
Is a lightweight material, therefore, it can span long distance
Does not require formwork, unlike concrete which makes it cheaper than reinforced concrete
Is easily erectable which speeds up the construction process and it is easy to assemble/disassemble the structure
Has less repair and maintenance costs compared to concrete
There is a variety of connections types (welds, bolts, rivets)
Has less fire resistance compared to concrete, therefore, it needs fireproofing to resist fire damage; can melt at very high temperatures
Has buckling problems
Exact measurements have to be known before the transport and delivery of steel because the steel fabrication company does the manufacturing off-site (prefabrication)
For the simply supported floor beam with point loads (live and dead loads) at midspan as shown below, select the lightest W-shape beam using LRFD method (factored loads). The beam is laterally braced at the supports and at midspan.
Figure : Steel Design example 2(selecting the lightest beam)
For the pinned-pinned steel column shown below, calculate: (a) the critical load, PCR and critical stress, FCR, and,
(b) the available strength in axial compression,ΦPn, and (c) the available critical stress, ΦFCR.