I. Clearwater concrete building.
1. Architectural style.
As a form of architectural expression, fair-faced concrete architecture first appeared in Japan in the 1960s, and its successful application began in the late 1980s, and then gradually appeared in Germany, the United States and other European and American countries, thus becoming a new architectural school. Japan was the first country in the world to adopt this architectural form, and the first building with this design scheme was the Japan Olympic Stadium, which caused a sensation in the architectural world. However, because the process of preventing concrete from wet discoloration and the corresponding paint with good durability had not yet appeared, and the construction process at that time was to mix the ingredients of the paint into the concrete, the concrete surface turned black as if it was wet by rain, and there were only acrylic resin and polyurethane resin paint on the market at that time, whose durability was limited and the concrete surface turned yellow after a few years, so the popularity of this design was very short. The popularity of this design was short-lived. In the mid to late eighties, Japanese architect Tadao Ando was the first to challenge and create this new form of architecture in a building in Tokyo, and became a world-renowned architect with his success. After that, many Japanese architects followed suit, thus triggering a second climax in the design and application of plain concrete, and the style of fair-faced concrete is increasingly respected and accepted in Japan and many countries around the world. The main reason for the success of the application in the late 1980s was that Asahi Glass Coatings and Resins Co., Ltd. developed a new variety of AC coatings that prevented moisture discoloration and used room temperature curing fluorocarbon resin coatings, which made it possible to maintain clear concrete buildings for 10 to 20 years without damage. To date, the company has an impressive track record of 8 million square meters as a market leader in the AC method for clear concrete protection.
This form of architectural expression can completely and effectively retain the natural color and mechanism of the concrete building itself, with a simple appearance, which is a manifestation of returning to simplicity and nature, reflecting the harmony and perfection of architecture and people and nature, and realizing the yearning and return to pure nature rooted in people’s heart; it does not seek luxury, does not fall into the commonplace, but has a strong personality, with the style of everyone, representing the simplicity The fashion, distinctive personality and surging passion.
2. Technical composition.
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 absorption rate is large, such as no protection, through the wind and rain, concrete in the natural environment will suffer from sunlight, ultraviolet rays, acid rain, oil and other damage, and gradually lose its original face, concrete will also be increasingly neutralized and destroyed with the passage of time, its surface effect will become increasingly dirty, affecting the outlook. Therefore, transparent protective spraying on the concrete surface can not only solve the problem of protecting concrete, making it more durable, but also can play a role in preventing pollution, keep clean, not because of water absorption and color darkening, so the clear concrete building in the rain can still keep the color unchanged, unlike some overpasses, as soon as it rains, dirty, so it is also known as dry spraying.
II. The concrete pouring construction.
As the main body of the building, the quality of concrete pouring is the most effective link of concrete transparent protection, its good or bad directly determines the final decorative effect of clear concrete walls, according to industry sources, the final effect of 60% depends on the quality of concrete pouring, 40% depends on the later transparent protection spray construction. Therefore, it is a great challenge for building structure contractors to pour concrete with high standard and strict requirements to meet the requirements of decorative concrete, so attention should be paid to.
First of all, the formwork must not be chosen to cause wall staining, or to affect the uniform setting of the concrete and cause the walls to vary in color, or the wood fibers to stick easily to the walls when the panels are removed. The formwork must be of good quality and suitable for the pouring of quality concrete, which is the most basic principle for choosing the formwork.
Second, it should be carefully poured to ensure the quality of concrete construction.
III. Clearwater concrete transparent protection spraying process (Bonnflon AC Dry Coating System)
1. Overview.
This is a highly durable room temperature curing fluorine resin (Bonnflon) transparent (or translucent) coating, spraying on the surface of concrete so as to play a long-term protection of concrete from external environmental damage and maintain the natural mechanism of concrete and texture of the spraying process. The main features are as follows.
1) Super weathering resistance: Due to the excellent weathering resistance of fluorocarbon resin, the concrete surface can be kept maintenance-free for 15 to 20 years;
2) Outstanding water repellency (waterproof): The primer has excellent water repellency and prevents water from entering the concrete, thus protecting the concrete;
3), Return to the natural surface effect: it can maintain the natural color, mechanism and texture of concrete, and achieve a unique, personalized surface effect;
4) Prevent concrete cracking: the whole concrete wall surface is protected by fluorocarbon resin coating, avoiding cracks caused by concrete attack;
5), Very effective in preventing concrete neutralization: concrete neutralization is the biggest hazard of concrete deterioration, the efficient protection of fluorocarbon resin coating can prevent concrete from neutralization damage.
2. Categories can be classified according to the coating effect.
Completely transparent coating method (Clear Coating)
Color Clear Coating
Water-based fluorocarbon resin coating (Water Base Type)
Oil-based (solvent-based) fluorocarbon resin coating (Solvent Type)
3. Wall base treatment.
As mentioned before, to achieve the best surface mechanism effect with this process, the most important thing is the quality of concrete pouring, and the poured concrete wall should reach the level of flatness and can be painted without repair. However, as the construction of concrete requires the joint work of many people and machines for construction. And the structural work may span several distinct seasonal changes.
Therefore, it is very difficult to achieve the desired quality and effect of decorative concrete. Therefore, after the main structure is completed and the quality of concrete pouring has been set, the base treatment of the wall surface is crucial, and the quality of the treatment directly affects the final spraying effect.
A. Cleaning of the wall surface.
B. Repair of the wall surface for the defects on the concrete surface, in principle, the fewer the number and parts of the repair, the better.
Quality standard: Since there is no Chinese national standard yet, the industry experience is used as the quality standard for the time being.
1), Grass-roots treatment: To achieve a flat wall surface, the color is roughly uniform, no holes greater than 5mm, no cracks greater than 0.5mm, the height difference between the wrong part of the mold is less than 3mm, no obvious repair traces, the original mechanism of the concrete surface is still visible, the color is roughly uniform from the overall view;
2), Primer: Spraying uniform, no omissions, to achieve a slightly deeper wall color after spraying, through the wall surface waterproof test to achieve no water seepage;
3), Intermediate coating: spraying evenly, no omissions, after spraying the wall color is deeper than the previous procedure;
4), Transparent cover coating: Spraying uniform, no omissions, spraying the wall surface decorative effect is obvious, the formation of stable and uniform protective film, the overall observation of the wall surface flat, clean, uniform color, no color difference, and vaguely maintain the original concrete surface mechanism effect, through the wall surface waterproof test to achieve no water seepage, water splashed on the wall surface, the color does not change, no deep, no wet.
