Application of the stone

In many aspects, for example, color, texture, construction, and the different fields of material obtain, etc. , all have their own unique conditions; therefore, while selecting the material should based on its purpose

Overall, the following aspects should be considered in selecting the stone:
First, Budget Cost

Stone belongs in natural ore and in different stone due to its different quality, quantity, and exploitable ground etc., which will cause its price different apparently. Therefore, while in initial stage of selecting use, vendor and designer should know its cost splendidly.

Second. Expression of Aesthetics

In selecting, such factors as the color, pattern and texture of the stone, belongs to subjective aspect, which often different in vendor and designer’s interest. However, the more understanding the natural stone deeper, the more outstandingly flexibly in designing the expression of the craftsman will be appeared.
There are three classifications of the ore forms: igneous rock,metamorphic rock. The commonly used construction stone in here is mainly with the marble (Metamorphic rock) and the granite (Igneous rock). Generally speaking, the stone of the marble has more abundant color and pattern; and the demonstration of the texture is mainly on smooth and soft. However, color of the granite has few changes on color and pattern, but there is more flexible appearance in texture (Such as table 2-1). In addition, the granite seems comparatively solemn and classical on the feeling of the whole.

Third, Stone Quality's Control:

1. Material's even and intact:
Should avoid such questions as splitting, black scar and color difference, etc..

2. Compositions of the stone :
(1) Avoid containing the harmful substance such as too high vulcanization iron, iron oxide rust, salt, charcoal quality and clay in the stone.
(2) Prevent the stone from holding compositions of radiating.
(3) Avoid containing too high hot coefficient of expansion, heat conduction and mineral composition of conductive rate in the stone, in order to keep away from the dangers of the crackle, heat conduction and electric conduction.

Fourth, Durability's Analysis

While adopting the stone as renovation materials, generally hope the stone can have the same vitality with the structure; especially for outer wall and ground fit up, it is even important for its durability. For the reason that, having a good stone of durability, not only can assure the beauty of building's appearance, but also can guarantee the firm and security of the stone, to avoid dropping and injure pedestrians.

However, for stone, building outer wall and level ground which install by stone, have a heavy test for itself:

1. As regards physics respect:
The stone must bear the destruction of numerous external forces, which including gravity, shakes, wind-force, temperature varying, wears and tears, loading, etc..

2. As regards chemistry respect:
For the chemical corrosion, which includes water, dissolves, dehydrates, acid, reduces and carbonate, etc.

3. Actually the stone with steady molecular structure, uncovered it after the atmosphere, which cause encourage cooperation among different mineral substances of stone's forming deficiently. For example, when the lime stone meets the acid (Sumptuous acid gas and rainwater), and dissolve it to the calcium sulfate after, cause collapse of the sandstone, etc.

Therefore, once selecting the stone should try to choose the hole to be distributed even, the aperture is small, low absorbing water rate, and high hardness and compression strength, could reach the durable demand. (Consult the attached table 2-2 )

1. Choose stone which has low absorbing water rate
The higher the absorbing water rate, the easier to absorb moisture, which leads to volume expansion; and because absorb the soluble composition or salt in the air, make the stone corroded, which cause the lowering of the intensity of stone.

2. Choosing the small aperture, and the low hole rate of stone
The higher the hole rate, the larger the absorb water rate, and easier to suffer weathering and reduce its intensity.

3. The stone with bigger proportion, though compression strength is relatively great, will increase the load of the structure, and decrease a resistance for the earthquake.

4. While selecting the stone with directionality bedding (Such as the slate, shale), must be pay attention to its different structure intensity of direction.

Five, Consideration of the position use:

As the stone is used on outer wall, ground level, the skyscraper or other external environmental special character, the selecting of the stone type in use is becoming more important.

Six, Principle of installation

Eight, cooperation of the source of the stone and whole project progress