Essay On Concrete Floor

A monolithic reinforced concrete floor is one unbroken solid mass, between 100 and 300mm thick, of in situ reinforced concrete. In this project, thickness of the concrete slab is 250mm. Formwork is required to support wet concrete for at least a week after it has been placed. The steel reinforcement is laid out on top of the support and raised 20mm or more above the formwork by means of small concrete blocks, wire chairs or plastic spacers, which are tied to the reinforcing bars with wire. The wet concrete is then placed and spread over the reinforcement and the formwork. It is compacted, vibrated and leveled off.

Steel reinforcing bars are cast into the underside of the floor with 20mm or more concrete cover below them to prevent the steel rusting and to give it protection in case of fire. The thicker the concrete cover to reinforcement, the greater the resistance of the floor to fire. A combination of high tensile steel and mild steel reinforcement is used. The high tensile steel is usually positioned at the bottom of the concrete floor to withstand any tensile forces.

The main reinforcement usually consists of 12mm diameter high tensile steel rod spaced from 150 to 225mm apart, and

They are direct installation and plywood sub-base method. Plywood sub-base method is applied to accommodate slight unevenness of the screed. In this method, plywood is used as sub-base to receive timber flooring. However, this method cannot solve the problem of the uneven levelness of the floor screed. Proper supervision and good workmanship should be given to achieve the required levelness of the floor screed. The plywood is adhered and nailed to screed. Precaution and care should be taken in order to prevent any damage to any embedded M&E services where applicable. The adhesive is used to hold the plywood in-place and minimise hollow sound resulted from uneven floor screed and voids left between the plywood and