Six key points in the selection of stone curtain wall

Although the variety of stones that can be used in construction has reached an astonishing more than 6,000 types, if the classification of stone systems can be divided into five categories: granite, marble, sandstone, slate, artificial stone.

So what kind of stone does the stone curtain wall usually use?

According to the current world stone wall specification, the stone used should consider the following requirements:

1, anti-corrosion and durability

In general, a stone having a high silica (SiO2) content has high strength and durability, and a stone containing more than 50% of silica (SiO2) is suitable for use in an exterior wall. On the contrary, stone with high content of calcium oxide (CaO) is easily corroded by gases such as sulfur dioxide in the atmosphere. Such stone is used for curtain wall, and more perfect surface treatment is needed to take more effective anti-corrosion measures.

2, density and uniformity

1. The same type of stone, the volume density has a certain distribution range. Generally, the stone with a large bulk density is dense, high in strength and durable. Stones having a bulk density ρG of less than 2.1 g/cm3 have a low density; ρG = 2.1 g/cm3 to 2.5 g/cm3 is a medium density; and ρG ≥ 2.5 g/cm3 is a high density. The stone used for the curtain wall should have a density that meets the requirements of Table 1. 2. The stone used for the curtain wall should be more uniform in texture.

(1) There should be no weak interlayer or weak veins in the stone.

(2) Rocks with a layered pattern should not have coarse, loose, porous stripes.

(3) Porous rock should not be too large in pore size and too deep in pores. The number of holes should not be too much. Otherwise, sealing measures should be taken.

3, high strength

As an important indicator of the strength of the stone, it is dry.

The average fm of the bending strength test of igneous rock (including granite) should not be less than 10N/mm2. When the bending strength of the test piece is less than 8 N/mm2, the batch of stone should not be used in the curtain wall; other stone fm should not be lower than 4 N/mm2, when the bending strength of the test piece is less than 3 N/mm2, the batch of stone should not be used in the curtain wall.

Sedimentary rocks sometimes have inconsistent strengths in all directions. At this time, the strength along the main direction of the stone panel should meet the above requirements.

4, freeze-thaw coefficient

After the stone has undergone freeze-thaw cycles, the strength is reduced. The freeze-thaw cycle test of granite is carried out according to the national standard GB9966.2. The ratio of the strength to the original strength after the freeze-thaw cycle is called the freeze-thaw coefficient. The stone used for the curtain wall should have a freeze-thaw coefficient of less than 0.8.

5, water absorption rate

The water absorption rate of stone should be less than 0.8%

6, radioactivity

The stone used for the curtain wall shall have the radioactivity in accordance with the requirements of Grade A and Grade B stone in GB6566 of "Limited Radionuclides for Building Materials".

[Scan the QR code below, pay attention to the WeChat public number "Jiuzheng Stone Net "; you will receive the latest stone news, information, business opportunities! What are you waiting for? Join the China Building Materials First Network - Stone Group: 65406142]

Gate

Hebei Haiao Wire Mesh Products Co., Ltd. , https://www.haiaowiremeshfencing.com