Description
Fair Faced Concrete is a new sort of concrete that’s been evolving in response to public desire for architectural decoration, and it’s becoming more common in modern construction projects especially in India.
Types of fair-faced concrete:
We can categorize fair faced concrete into three types as follows:
- Standard plain concrete
- Form faced concrete
- Decorative fair-faced concrete
Factors to be considered for obtaining Fair Faced Concrete:
1. Formwork Planning
Proper planning of Formwork is very crucial for achieving Fair Faced concrete structures. From the Tie holes and Plywood impression, all the components impression along with the Design data should be considered carefully.
2. Uniform Colour of the Mix
The concrete mix must have good colour consistency, good cohesiveness so it does not segregate and good workability for ease of placement. Colour consistency is achieved by keeping all the constituent materials of the mix the same, with the same proportions and colour and with minimal variation.
3. Selecting the Form Face
The beauty of the surface finish lies in the type of Formwork System used & the sheathing member used.
Nav Nirman uses H-Beam System with sheathing as Birch Plywood which gives a proper finish for fair faced concrete.
4. Concrete Placing and Compaction
This is critical for walls and columns. Good workmanship, placing and compaction technique will result in a blemish-free surface finish.
Compact and vibrate the concrete in 500 mm layers to release all the trapped air. When compacting the concrete, insert the vibrator head quickly into the layer and hold for at least 20 to 30 seconds to release all the trapped air and to consolidate the mix.
5. Formwork Pressures for Wall Shutters
Refer to CIRIA 108 for formwork pressure tables. Design for the correct pressures for concrete mixes with GGBS or PFA replacement cements and with admixtures. Consider the design pressures for a rate rise of 2m/hr vertically in winter at a temperature of 10 deg C and a rate rise of 3m/hr in summer with a temperature of 15 deg C.
Limit the extension of the tie bolt to not more than 2mm across the width of the wall to reduce grout loss, lipping, black eyes and loss of definition of the tie cone hole. This is a frequent problem in concrete construction.
6. Good Workmanship Tips
Apply release agent very sparingly on the form face. Spray it on and wipe it over with a clean cloth and leave just a fine even coating. Excessive use of release agent will remove the surface skin of the concrete and discolour the finish and reveal many clusters of small blowholes.
Conclusion:
Fair-faced concrete has steadily gained popularity as a type of decorative concrete. Nav Nirman has the technical expertise to create formwork for even the most challenging fair faced concrete requirements. Our depth of expertise enables us to design and manufacture formwork solutions based on standard components or by custom manufacturing a solution in our factory from technical speciation’s supplied by architects, engineers and designers.