Structural engineering is the branch of engineering which involves mainly analysis and design of concrete, steel or timber framed structures like, bridges, dams, tall buildings, stadiums, towers, retaining walls and foundation.
The two main areas of structural engineering are:
- Structural Design
- Structural Analysis
Good knowledge of structural material and behaviour is required, under different types of loading. As construction materials, concrete and steel are commonly used. In addition to these, pre-cast & pre-stressed concrete are also used. High performance concrete (HPC) is a kind of special concrete which provides solutions to certain situations.
Structural design comprises repetitive cycles of preliminary design, Structural analysis (computation of stress, strain, bending forces, deflection); refined analysis, design revisions & alternatives.
Any structure is made up of different types of small elements:
Columns are elements that carry only compression – axial force – or both bending and axial force (which is precisely called a beam-column but basically, just a column). The design of a column must examine the axial capacity of the element & the buckling capacity.
Columns and beams are termed as line elements & are frequently represented by simple lines in structural modelling. A beam may be defined as an element in which one dimension is much larger than the remaining 2 and the applied loads are generally normal to the main axis of the element.
AÂ trussÂ is a structure including 2 types of structural elements; tension members and compression members. Maximum trusses useÂ gusset platesÂ to attach intersecting elements. Gusset plates are comparatively flexible & lessenÂ bending momentsÂ at the connections, thus allowing the truss members to carry primarily compression or tension.
Plates convey bending in two directions. Plates are taught with continuum mechanics, but because of the difficulty involved they are commonly designed using a codified empirical approach, or computer analysis.
Shells stem their strength from their form, and transmit forces in compression in two directions. An example is a dome.
Â Arches transmit forces in compression in only one direction that is why it is suitable to build arches out of masonry. They are designed by confirming that theÂ line of thrustÂ of the force stays inside the depth of the arch. It is mainly used to upsurge the bountifulness of any structure.
Catenaries derive their strength from their form, and carry transverse forces in pure tension by deflecting. They are almost always fabric or cable structures. A fabric structure acts as a catenary in two directions.