A concrete frame is one of the most common frame use in modern construction of building structures, it comprises of columns and connecting beams that forms the structural ‘skeleton’ of a building. The beams and columns is typically constructed on a concrete foundation and is used to support the building’s floors , roof, walls, cladding etc.
Beams as the horizontal load -bearing members of the frame are classified into two:
- Main beams: This are the beams transmitting floor and secondary beam loads to the columns. While
- Secondary beams: This are the beams transmitting floor loads to the main beams.
The materials used as walls for concrete frame structures are heavyweight masonry options and lightweight options. were the heavyweight masonry could be brick, blockwork, stone, and the lightweight are drywall, timber and etc. Similarly, any kind of cladding materials can be used to clad concrete frame structures.
Reinforcement bars (rebar) are needed in concrete due to it low tensile strength. The material mostly used in reinforced concrete are steel bar or mesh of steelwires, their function is to strengthen and hold the concrete in tension. The reinforcement bars are to be embedded to the concrete before it compacted to improve the quality of the bond with the concrete.
Also check: Reinforcement in building construction
Columns are the vertical members of the frame,They transmit the beam loads down to the foundations. and they are the
building’s primary load -bearing element.
Concrete frames can be precast (manufactured off site), or cast on site.
The precast concrete frames are typically used for single- storey and low-rise structures where the concrete members are carried to site and places them into position to construct the frame.
Slip form is a method of construction in which concrete is poured into the top of a continuously moving formwork. As the
concrete is poured, the formwork is raised vertically at a speed which allows the concrete to harden before it is free from the
formwork at the bottom.. Slip form is most economical for
structures over 7 storeys high such as bridges and towers, as it is the fastest method of construction for vertical reinforced concrete structures, but it can also be used for horizontal
structures such as roadways.