Many architects like to use fair-faced concrete, so what exactly is fair-faced concrete? Fair-faced concrete is also called Architecture Concrete, Exposed Concrete, or Fair Faced Concrete (decorative concrete).
Its most important feature is that after the concrete is poured, there is no longer any painting on the outside, and no tiles, stone, and other materials are pasted, which is a way to show the plain face of the concrete. However, due to the fear that it will be soaked by rain or deterioration, it may be sprayed with a waterproof protective film.
As the technology continues to improve, the status of fair-faced concrete continues to rise in the minds of architects – the surfaces are becoming smoother and flatter, the tones more homogeneous, and the joints on the surface neater. There is also a growing public recognition of the artistic expression of fair-faced concrete.
Fair-faced concrete is also known as decorative concrete, and as the name suggests, it is highly decorative. Its biggest feature in the construction field area with ordinary concrete is also its decorative nature. This article will introduce fair-faced concrete in detail.
Classification of fair-faced concrete
Fair-faced concrete is concrete that directly uses the natural texture of concrete after forming as the finished effect and can be divided into three categories: ordinary fair-faced concrete, decorative fair-faced concrete, and formlining fair-faced concrete.
Standard fair-faced concrete
It refers to fair-faced concrete with no obvious color difference and no special requirements for finishing effect.
Decorative fair-faced concrete
It refers to fair-faced concrete with the same surface color, formed by the combination of the regularly arranged apparent seam, zen seam, split bolt hole, etc., with natural texture as the finished effect.
Formlining fair-faced concrete
It is fair-faced concrete with decorative patterns, inlaid with decorative pieces or colors.
Technical points
In order to show the best effect of clear concrete architectural style, the most important thing is still the pouring, maintenance, and treatment of concrete walls. As we all know, the concrete surface has a large water absorption rate. If not made any protection, concrete in the natural environment will suffer from sunlight, ultraviolet rays, acid rain, oil, and other violations. Concrete will gradually lose its original face and be neutralized and destroyed with the passage of time. Its surface effect will become increasingly dirty, affecting its appearance.
Therefore, transparent protective spraying, also called dry coating, on the surface of concrete can not only solve the problem of protecting concrete and making it more durable but also can play a role in preventing pollution and keeping it clean, so that the fair-faced concrete building will not change its color because of water absorption and rain.
Four kinds of process
1）Pure transparent protection process
Scope of application:
a. The quality of clear water pouring is very good;
b. To completely retain the texture of clear water, allowing the existence of defects.
2）Transparent partial repair process
Scope of application:
a. The quality of clear water casting is very good;
b. To retain the texture of clear water and a small area of defects, and only repair the large area of defective parts.
3）Comprehensive coloring repair process
Scope of application:
a. General quality of clear water casting;
b. More serious color difference on the base surface and more honeycomb pockmarks.
4）Imitation of clear water process
Scope of application.
a. The quality of clear water casting is poor;
b. The leakage of slurry and sand appears to be more serious, the presence of large areas of honeycomb pockmarked surface or the construction of non-clear water concrete surface.
Construction essentials
The technical keys of clear water concrete construction are the following 3 points:
(1) Concrete ratio design and quality control of raw materials, the cement ratio used in each piece of concrete should be strictly consistent;
2) The fresh concrete must have excellent workability and cohesiveness, and absolutely no delamination and segregation is allowed;
(3) The origin of raw materials must be unified, the cement used must be the same batch of the same manufacturer as far as possible, and the color and grain gradation of sand and stone must be uniform.
Maintenance
If the fresh concrete is not properly maintained, the surface very easy to have micro-cracks due to water loss, which affects the appearance quality and durability. Therefore, the exposed concrete surface should be covered with sticky film or spraying-type maintenance film in time for moisturizing maintenance.
Split bolt hole, apparent seam, and zen seam
Split bolt hole
The most important feature of fair-faced concrete would be the split bolt holes. They are used for tension between the inner and outer formwork of the wall, to bear the lateral pressure of the concrete and other loads, and also as a pivot point for the formwork and its supporting structure. The holes left after forming are an important decorative point of fair-faced concrete.
1. Buttress screw
2. Sponge strip inlay
3. Transparent tape paper
4. PVC sleeve
5. Formwork
6. Aluminum beam
7. 50*100 wooden square
8. 10# channel steel
Apparent seam
The decorative lines are used to block the overall surface of fair-faced concrete to achieve unity between the structure and the decorative art of appearance. It is usually formed by inserting strips (apparent seam strips) attached to the formwork during concrete construction.
Zen seam
It is usually formed by a formwork joint, which divides and decorates the surface of the fair-faced concrete further than the apparent seam. It is filled with foam rubber between the two formwork pieces and sealed with tape underneath.
Apparent seam is also called horizontal seam and Zen seam is also called standing seam.
Based on the above characteristics of fair-faced concrete, the size of the formwork, and the spacing of the split bolt will affect the effect of the building wall. Therefore, when designing a fair-faced concrete building, architects need to include split bolts in the design consideration.
To know about the advantages of fair-faced concrete, you can read this article.