Concrete Slab Construction

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    There are various concrete structural elements/ members like the footing, column, beams, and slabs. Among them, the slab is the first structural member to take up the load directly from the objects. So it needs to be constructed in such a way to take up the bending moment. There are various types of slabs that we have explained in the article " Concrete slab and its types ". In this article, we are concentrating on how we can make a conventional slab. Slab construction requires the following steps to get constructed in a good fashion.,

1. Preparation of Foam Work
2. Fabrication and Erection of Steel
3. Concreting of Slab
4. Removal of Foam work 
5. Touch up works
   
6. Curing

Fabrication of Foam Work

     Form work which is also known as the shuttering work is done with the help of plywood sheets or with the help of steel sheets. These sheets were arranged in such a fashion all the base and sides of the required dimensions of the slabs and beams were created for the pouring of the concrete. In Simple words, the formwork forms the mold for the concrete slab. The individual sheets were supported with the help of span vertical members and runner pieces with required nails to prevent the sheets from falling to the ground and to prevent undulation in the slab foam work. There will be small gaps between the sheets that need to be packed with packing tape so that it prevents the concrete from segregation. Waste Oil or any lubricating liquid needs to be given to the concreting surface of the foam work to prevent direct contact of the foam work with concrete to prevent sticking of sheets in the concrete while removing

Slab Foam work supported by Vertical members

Fabrication and Erection of Steel

    The Beams were concreted along with the slab hence the reinforcement of the steel for the beams needs to be made parallelly when the slab foam work is prepared. Then the beams steel are erected in their respective places along with the slab reinforcement. 

Slab Reinforcement over a Slab Foam Work

Concreting of slab

 

    Before concreting all the required arrangements for concreting need to be done like labor, Materials, etc. Let's take for example you are planning to do the concreting of the Slab by using Ready mix concrete(RMC). Then you need to inform the RMC plant about when and how much concrete you need that needs to be conveyed to the RMC Plant along with that the equipment that is needed also needs to be in the ready position. But if you are planning to prepare the concrete mix manually, the workforce that is needed needs to be prepared before concreting. Now the Concrete is poured into the prepared foam work to cast the slab.

A slab gets RMC from an RMC Plant through a Transit mixer

 

Removal of Foam Work

    The Foam work that is provided to cast the slab concrete needs to be kept undisturbed for up to 3 days of concreting with proper support of props(Jackey). After these 3 days, the foam work is removed and touch-up work and curing needs to be carried out.

Touch up Work

 

    After the Foam is removed the slab needs to be checked for whether it has any honeycomb or is damaged due it irregular handling of foam work etc needs to be checked and rectified. For those who want to honeycomb, it is nothing but a void that is created due to improper vibration and placement of the concrete. These voids were rectified with the help of a cement motor packed in it or through grouting.

Honey Comb in a Roof beam

Curing

 

    Curing of the slab is essential and for better strength of the concrete 28 days of curing is recommended, if not at least 7 days of curing is mandatory to get the required strength of the slab.

    Once the curing is complete we can move to the next stage of the construction. Various types of slab are used today which we explained in the article titled " Concrete slab and its types".