Theory of Built-up Sections

  • A built-up beam is also known as compound beam.
  • The built-up beams are used when the span, load and corresponding bending moment are of such magnitudes that rolled steel beam section becomes inadequate to provide required section modulus.
  • Built-up beams are also used when rolled steel beams are inadequate for limited depth.
  • In building construction, the depth of beam is limited by a space provided by the architect.
  • Drawing beam of small depth do not provide required section modulus. Therefore, plates are attached to the beams.
  • The strength of rolled steel beams is increased by adding plates to its flange which is one of the method forming built-in section.
  • The other method is to compound a number of rolled steel sections themselves.

Built-up Section

The built-up sections shown in figure’ A’ and ‘B’ are used for heavy loads and small spans.

Read moreTheory of Built-up Sections

Various types of Roof trusses for various spans

What is a Truss?

  • In Architecture and Structural Engineering, a truss is a structure comprising one or more triangular units constructed with straight slender members whose ends are connected at joints referred to as nodes.
  • External forces and reactions to those forces are considered to act only at the nodes and result in forces in the members which are either tensile or compressive forces.
  • Moments (torsional forces) are explicitly excluded because, and only because, all the joints in a truss are treated as revolutes.

In this article, we are going to discuss the various types of roof trusses in wood and steel and their uses in various kinds of construction.

Different types of Wooden and Steel Roof Trusses:

  1. King Post Truss
  2. Queen Post Truss
  3. Howe Truss
  4. Pratt Truss
  5. Fan Truss
  6. North Light Roof Truss
  7. Quadrangular Roof Truss

Trusses for large span constructions

King Post Truss

King Post roof truss (spans upto8M)
King Post roof truss (spans upto8M)
  • King Post Truss is a wooden truss.
  • It can also be built of combination of wood and steel.
  • It can be used for spans upto 8m.

Read moreVarious types of Roof trusses for various spans

Metal Lath Partitions | Metal Partitions

Expanded-Metal Partition or Metal Lath Partition

Metal lath and plaster have been used in both residential and commercial applications to partition interior space and in non-load-bearing exterior walls where appearance and durability are key.

Various Metal Laths
Various Metal Laths

Rib lath

  • Rib lath is widely used as a plaster backing on ceilings,walls and stud partitions.
  • Rib Lath is also ideal for refurbishing damaged or aged masonry walls
  • Material: Galvanized Steel for dry conditions.
  • Stainless Steel for external use and condition of heavy condensation or persistent damp.

Read moreMetal Lath Partitions | Metal Partitions

Column Bases | Design of Steel Structures

Column bases are structural elements used in the design of steel structures to transfer the column load to the footings.

Types of Column bases

  1. Slab base
  2. Gusseted base

Slab Base

Slab Base

Slab bases are used where the columns have independent concrete pedestals. A thick steel base plate and two cleat angles connecting the flanges of the column to the base plate. In addition to these, web cleats are provided to connect the web of the column to the base plate. These web cleats guard against the possible dislocation of the column during erection. The ends of the column and also the base plate should be mechanized so that the column load is wholly transferred to the base plate.

Area of base plate= (load of column)/(permissible bearing stress in concrete)

Read moreColumn Bases | Design of Steel Structures