Slab Concreting


Concrete Floor Slab Construction Process

  1. Assemble and Erect Formwork
  2. Prepare and Place Reinforcement
  3. Pour, Compact and Finish Concrete
  4. Curing Concrete and Remove Formwork

1st stage of formwork

2nd stage of formwork


The formwork shall be designed to withstand construction loads such as fresh concrete pressure and weight of workers and operators and their machines. Moreover, there are various construction aspects that need to be considered during the erection of formworks. For example, it should be positioned correctly, lined and leveled, joints sealed adequately, and prevent protruding of nails into the concrete, etc. Furthermore, different materials such as wood, steel, and aluminum can be used for the formworks of the concrete floor slab. Prior to the placement of reinforcement for concrete floor slab construction, inspect and check forms to confirm that the dimensions and the location of the concrete members conform to the structural plans. Added to that, the forms shall be properly cleaned and oiled but not in such amount as to run onto bars or concrete construction joints.

 Design drawings provide necessary reinforcement details, so it only needs the understanding to use designated bar size, cutting required length, and make necessary hooks and bents. After preparation is completed, steel bars are placed into their positions with the provision of specified spacings and concrete cover. 


slab reinforcement

Concrete should be deposited at, or as close as possible to, its final position in order to prevent segregation. So, Concrete placement in large and separate piles, then moving them horizontally into the final position shall be prevented.Moreover, the site engineer shall monitor concreting properly, and look for signs of problems. For example, loss of grout is an indication of improper sealing and movement of joints. Added to that, cracking, excessive deflection, level, and plumb, and any movement shall be checked and tackled to prevent further problems.


slab concreting

Furthermore, fresh concrete should be compacted adequately in order to mold it within the forms and around embedded items and reinforcement and to eliminate stone pockets, honeycomb, and entrapped air. Vibration, either internal or external, is the most widely used method for consolidating the concrete.


Curring

 After finishing the ended, a suitable technique shall be used to cure the concrete adequately. Slab curing methods such as water cure; concrete is flooded; ponded, or mist sprayed. In addition to water retaining method in which coverings such as sand; canvas; burlap; or straw used to kept slab surface wet continuously, chemical Membranes, and waterproof paper or plastic film seal. Regarding curing, it is recommended to remove formworks after 14 days.



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