Mankind has been using sand for a long time for construction needs; without it, a house cannot be built. It is actively used in dry building mixes, which are sold in stores or as a component for the preparation of cement mortars. Building sand is used depending on its density, for example, certain types are used to create masonry mortar, others in order to screed concrete.
Sand is a non-metallic building material with a loose consistency. As a rule, this is a mixture of grains of 0.14-5 mm in size, which were formed during the period of natural destruction of rocks. There are several types of sand. They are characterized by different from each other content of small particles of clay or just dusty elements.
The cleanest of them and the highest quality is river sand. Sea is worse, since its composition already contains salts, from which it must be cleaned. Quarry sand and mountain sand are distinguished by the presence of unwanted clay, which means that the quality of the product is lower. Sand mainly has the following composition: quartz and feldspars, as well as impurities in the form of silicates and all the same clay.
To characterize this building material, there is such a thing as sand density. It is estimated by the coefficient of porosity. For example, fine-grained varieties have an indicator of 0.75. The density of building sand, its quality is always determined by the presence of clay in it. Builders love to work with a unique cleanliness - a river product. It has a density of 1.3 tons per cubic meter. The density of sand with clay content is higher and is already 1.8 tons. In the same volume.
This material has been the basis of cement and concrete compositions for many years. It is very in demand when laying roads, when blowing glass products and in agriculture.
In construction, the concept of density is of fundamental importance, which is the ratio of the mass of sand to its volume, it has units of measure: g / cm3 and kg / m3. The natural bulk density of sand is 1300-1500 kg / m3.
For bulk building materials, this indicator is variable and depends on the degree of compaction. This means that the same amount of product takes a different volume. The density of sand is invariably dependent on humidity, and any changes in it affect the bulk density. With increasing humidity, the grains of sand become covered with a layer of water and, accordingly, the volume of sand increases sharply. It is the bulk density of the sand with moisture fluctuations taken into account when calculating the dosage of sand for the required volume. If this factor is not taken into account, the building mixture will not have the necessary margin of safety and, as a whole, the engineering structure will be of poor quality.
Nowadays, pre-filled sand is mainly used , it is mined simply by washing quarry sand. This is done in this way: clay and dust are washed out of it with a large volume of water.
The density of building sand also depends on the grain structure. For example, a high indicator directly indicates that its composition contains dense, especially durable and frost-resistant grains. It is such a material with a high coefficient that is indispensable for construction in permafrost. It is the basis of high-strength concrete, with excellent indicators of frost resistance.
The density of quartz sand in a loose state is characterized by an indicator of 1500 kg / m3, but can increase to 1700 kg / m3. It is characterized by the best hygienic characteristics and is a washed and calcined dry natural material. When used in construction, high hygienic characteristics of the home are ensured. The density of quartz sand is a very important parameter that is taken into account when carrying out construction work.