An image wall or image platform is a facility in a building that has both decorative and functional functions. Many image walls or platforms are embedded with corporate logos. And the outdoor image wall is the first impression that people have of this building and this enterprise. Due to the harsh conditions of outdoor exposure to sunlight and rain, these image walls generally use durable materials such as stone, glass, metal, etc. The use of stone is also the highest. This is because there are a wide variety of stone materials with strong selectivity and processability, which can meet various decorative styles.
1、 Common issues
However, if we pay attention to the image wall around us, we will find that there are very few things that do not go wrong. Usually, the expected decorative effect can be achieved in the first few months after installation, but then various edges, fractures, and water spots appear. The meaning of this’ image ‘is greatly diminished by the image wall.
1. Degumming
2. Dealkalization
3. Water spots
2、 Cause analysis
In fact, from a distance, the Indian red on the front of this image platform seems to be quite good. But this is mainly due to the high density and low water absorption of Indian red, which itself has strong resistance to pollution and disease. But under harsh outdoor conditions, even the hard granite in our impression does not always possess this resistance. The golden hemp behind this platform has severe water stains, which affect its decorative effect.
Firstly, it is degumming. But for outdoor stone installation, marble glue cannot be used. Because marble adhesive is a hard adhesive, it has high strength after drying and can firmly fix the stone. Yunshi glue is acceptable for indoor environments where the temperature difference between the four seasons is not significant. However, when used outdoors with a huge temperature difference of over 30 ℃ in summer and below -10 ℃ in winter, besides the rapid aging and failure of the glue itself, there is also a serious problem.
That is, after being filled with hard glue, the deformation of the stone caused by such a large temperature difference cannot be buffered. The stress of Thermal expansion is very huge and must be extended. If the extension is not available, the dry hanging stone may be deformed and crushed, while the wet pasted stone may peel off and fall off from the bottom cement. Therefore, marble adhesive is not suitable for outdoor stone installation.
Stripping of stone
When the stone is peeled off and the marble glue falls off, rainwater will seep into the bottom of the stone along the gap that has lost its sealing, bringing out alkaline substances and forming a re-alkali. Long-term soaking in rainwater forms water spots.
3、 Preventive methods
1. Outdoor installation requires sealant
The sealant is a kind of soft glue. In addition to its strong adhesive force, it can well match the stone deformation caused by the large outdoor temperature difference in four seasons and the circulating freezing and thawing of rainwater. It can provide a buffer zone for the stress of the Thermal expansion of the stone and prevent the stone from breaking and falling off.
2. Reserve 1~1.5mm Expansion joint during installation
The Thermal expansion of outdoor stones is very deformed. Even if soft glue sealant is used, there is not enough space. Therefore, such outdoor plates cannot be closely jointed, but enough 1~1.5mm Expansion joint shall be reserved.
3. Take protective measures
Granite is hard and durable, and when used in outdoor environments, few people are willing to pay the cost to maintain it and provide it with protection.
But what we need to say is that the emergence of stone problems is a systematic problem, and the solution to stone problems is also a systematic problem. If you have a headache on stone, it cannot solve the problem. It is best to follow the principles of stone care technology and do what needs to be done during installation so that later use will naturally be worry free and reassuring. Stone protection is an important aspect.
① Smooth fluorine protection
Providing protection for outdoor stones, due to extremely harsh environmental conditions, ordinary water-based and oil-based protective agents are no longer sufficient. It is still most suitable to use fluorine-based protective agents, which add fluorine elements and form stronger bond chains, making them suitable for harsh outdoor conditions.
② Seal and protect the rough surface
For rough stones, directly use surface sealing protective agents, such as VD stone polishing protective agents. After being applied, it has excellent waterproof and anti-fouling functions, which can prevent unsightly water spots, alkalinity, and other phenomena. The duration can reach over 10 years.
