Building Structural Systems - CIVIL PRODYOGI


Building Structural Systems

Any structure under consideration is made of both the structural elements and non-structural elements. The structural elements are elements that are load carrying units. For.example columns and beams. Non-structural elements are those that do have a major role in load carrying, these involve false ceilings, partitions, doors etc.

Structural Systems in Civil Engineering

The structural system is a combination of all the structural elements. The main function of the structural system is to resist efficiently the gravitational and the environmental load action. This is done through proper transmission of resulting forces to the supporting ground. This process has to be carried out without affecting the geometry, integrity and the serviceability of the structure.

Most of the structural elements have to be considered in a view of simplified analysis. This can be either one-dimensional elements or two-dimensional elements. The one-dimensional elements will include elements like columns, arches, beams and truss elements. Slabs, shells, and plates will come under two-dimensional elements.

Some structural elements like shell - edge beam junctions or perforated shear walls will ask for rigorous analysis.

More Understanding of the topic can be done with an example:

We consider a reinforced concrete overhead tank structure. The structural system has three structural elements, they are:
  1. The Tank
  2. The staging
  3. The foundation
Fig.1. Water Tank Structure Constructed

These three elements are designed and constructed in separate stages. Say, the tank will be made up of dome-shaped shell roof, a cylindrical wall (side wall), a conical portion below the lower ring beam. the main ring beam, a flat circular base slab, these are supported by columns of the staging.

The staging will have beams and columns arranged in a three-dimensional fashion. This arrangement is fixed to the foundation. 

The foundation is a raft type. This consist of the slab that forms the shape of an annular ring. These are stiffened by the ring beam on the top. This is resting on a firm soil below. 

Loads acting on the Structural Systems

The loads that are acting on the structural systems are
  1. Dead Loads : The loads due to the sel-weight
  2. Live loads : Load from the water in the tank and the maintenance on the roof
  3. Wind Loads: Loads that is acting on the surface areas of the tank and the staging elements
  4. Seismic Loads: Load due to earthquake induced force