BUILDING FRAMES

 BUILDING FRAMES

The framing of a multistorey building varies on the basis of it's type and function. Typically multistoried buildings consist of offices, residential flats, hospitals, etc. For these types of buildings RCC is preferred as the catalyst for construction reason being it provides good strength and is economical ( if the building is less than 20 storeys ).

However, if a building has more than 20 floors, then it's debatable if RCC or steel will be used as a means of construction. Exceeding 20 floors, steel becomes more cost efficient than RCC and can also be used to lay down the framing in a lesser time frame than RCC. Hence for multiostorey buildings, steel is used to lay down the frames for columns, beams and girders. 

FRAMING OF A BUILDING

A building frame consists of columns, beams and girders which support floor and roof load. This type of building frame is known as Beam and Column frame. From storey to storey, the columns remain consistent with beams and girders attaching to them as we proceed. 

For the flooring we use wood, concrete or steel ( if required ) and this in turn is supported on the floor beams. 

NOTE: BEAMS WHICH SUPPORT THE EXTERIOR WALLS ARE KNOWN AS WALL BEAMS OR SPANDREL BEAMS.

ABILITY TO WITHSTAND LOADS

In general the ability of a multistorey building to withstand all kinds of loads depends upon the rigidity of connections between the columns, beams and girders. Apart from the vertical loads which consists of the dead loads ( weight of the individual components of the building ), the building is subjected to lateral loads. To resist these, requirement arises for the components to be completely rigid. 

To achieve this, columns can be continuous for upto 2-3 storeys, beyond which they may be spliced and connected to the beams and girders. 

For optimum utilization, the columns are arranged with flanges, parallel to the longitudinal axis of the structure, since that is the best way to resist the transverse loads.