Properties of good building stone

 

1. Fire resistance

2. Porosity and water absorption

3. In terms of dehumidification

4. In terms of weather resistance

5. In terms of resistance

6. In terms of weight

7. In appearance

8. In terms of structure

9. In terms of difficulty

10. In terms of toughness

 

 

Not all building stones used in construction are necessarily in ideal condition. For example, a stone may meet the requirements for strength and durability but may not be acceptable in other respects. As a result, it is one of the tasks of the project engineer to select a stone that fits the needs of the project.

A good building stone should have these characteristics:

 

 

Building stone must be free of calcium carbonate, iron oxides, and minerals of varying thermal coefficients. Igneous stone undergoes major decay because quartz decomposes into fine components at temperatures of about 575 ° C. In contrast, limestone can withstand higher temperatures, for example up to 800 ° C will decompose at higher temperatures.

 

 

Porous building stones are by no means suitable for use in construction, especially if they are to be exposed to the air in exterior facades. Acid rain reacts with the components of the stones and causes them to collapse. In cold areas, water in the cavities of the stones It stays frozen because water increases in volume due to freezing. This expansion causes the rocks to disintegrate.

The porosity of the stones should be tested and the porous stones of the trunk should be used in places that are not exposed to any cold rain or any kind of moisture. Water absorption is directly related to the porosity of the rock. The higher the porosity of the rock, the more water is absorbed and leads to the destruction of the rock.

 

    It is ready in some types of rocks along with their maximum water absorption (in percentage)

Sandstone: 10

Limestone: 10

Granite: 1

Shale: 10

Gneiss: 1

Rock: 1

Quartz: 3

 

 

 

All freshly eaten rocks contain a certain amount of moisture, which is called natural mine moisture, which makes them softer and easier to work on. A good rock should lack the natural moisture of the mine. The moisture of the mine can be taken naturally from the rocks. This process of removing moisture is called dehumidification. An interval of 6 to 12 months is usually sufficient for proper dehumidification.

 

 

This parameter indicates the resistance of the outer part of the rock to the weather.
 

The stones used in structures must have high strength and durability so that they do not decompose in the face of climate change and do not collapse. Normally, stones can withstand the forces applied to them by the structure, but In buildings where the forces are abnormal, their strength must be tested. Stones that have a good compact crystal structure have more strength. The compressive strength of building stones in practice in the range of 60 to 200 Nm / mm The square is located.

 

 

The specific gravity of building stones is directly proportional to their weight and strength. As a result, building stones with higher specific gravity should not be used in dams, retaining walls, piers and harbors. The specific gravity of a good building stone is between 2.4 and 2.8.

 

 

Building stones used in building facades should have a perfect and compact structure. Light colored stones are usually preferred to dark colored stones and it seems that facade stones should not be clay holes. , Have streaks or colored spots.
 

 

When a stone is broken, it should not lose its appearance, that is, it should have a uniform structure. The structure of the building stone should be free of any cavities, cracks or pieces of loose material. Rock stratification, commonly seen in sedimentary rock fragments, should not be visible to the naked eye.

 

 

When rocks are used for floors, substructures and river channels, the rocks are exposed to abrasion forces caused by water and friction. As a result, the stones that are to be used in such cases must be thoroughly tested before use.

 

 

Toughness is a measure of the amount of compaction that a rock can withstand. It should be strong enough when the rocks are to withstand the vibrations of vehicles and traffic on the roads.