Pebbles
The scientific name for pebbles is tumbled stone . It is a collection of a wide variety of natural minerals and rocks (most often quartz, dolomite or granite), polished to small smooth stones with the assistance of natural assistants - water and wind. The peculiarity of pebbles is that they owe their variety of colors, shapes and strength only to nature; humans have virtually no influence on the process of their creation and formation.
Between different types of pebbles, depending on the water in which the centuries-long process of their formation takes place, there are several differences, often significant. When treated with sea water, pebbles become smoother, sometimes even mirror-like, due to the constant ebb and flow of the tides, as well as the high salt content, which together act as an abrasive stone. Due to their strength, the most valuable pebble stones are Black Sea and Adyghe.
Pebbles are used for the construction of foundations, the construction of runways and highways, using them as a “cushion” for these objects, since due to their small size and high strength, they can withstand very heavy loads. Pebbles are also considered the best material for laying drainage systems and for backfilling access roads to beginning construction.
But pebbles are most widely used as a decorative material, since they are beautiful, environmentally friendly and, thanks to the variety of colors and shapes, an original decoration for interiors and landscapes: fountains, gardens, parks, artificial ponds and flower beds. Not only the facades and plinths of buildings are decorated with pebbles. It is also used for interior decoration (for example, a bathroom, even a kitchen apron).
Sand
Sand is a natural granular material consisting of small fragments of quartz, mica, spar and other minerals. It is formed due to the destruction of rocks under the influence of the environment.
There are many types of sand, but river and quarry sand are most often used in construction.
Features of river sand are:
- Lack of clay, which is necessary when building brick walls and creating screeds on the floor.
- High water permeability, therefore often used as a basis for drainage.
- It contains fewer impurities compared to other types of sand, which is why it is used for making glass.
River sand is also added to mixtures in the production of certain types of concrete, dry construction mixtures and mortars.
River sand contains smoother grains of sand compared to quarry sand, which makes quarry sand more suitable for concrete mixtures , since the uneven broken structure of its sand grains is stronger in connections with cement.
Unrefined quarry sand contains impurities, including clay, which gives it both advantages and disadvantages compared to river sand, depending on the type of construction work. Unrefined sand is rarely used, not for concrete work, since such a connection can be fragile due to various impurities in it, but it is actively used for backfilling (for example, to raise an area).
Quarry sand is used as a filler for concrete, in the production of reinforced concrete structures, as well as in the construction of highways and airfields. In the first case, it must be cleaned of impurities (mainly by washing), in the second case no cleaning is required.
Quarry sand is divided into seeded and washed - depending on the method of purification from impurities and larger fractions. Both types of sand preparation for construction remove soil, large as well as small dust particles, clay and other undesirable fractions.
The seeded sand is cleared of soil, large fractions, as well as dusty small particles. It can already be used for some types of concrete mixtures, for plastering work, and for laying foundations.
Washed sand is of higher quality than seeded sand, its characteristics are similar to river sand, it can also be used for wall masonry, screed, and concrete mixtures.
Sand also differs in the composition of its fractions - fine-, medium- and coarse-grained. Fine-grained sand is the most expensive sand, due to the high labor intensity of extraction, and is used for the manufacture of grouts and putties, self-leveling floors and other finishing materials. Coarse quarry sand is suitable for the production of paving slabs, curbs, for drainage, and is also used to create a cushion for the foundation.
Sea sand is as clean as river sand, but its extraction is not very active, as it requires much more labor. In addition, sea sand contains a significant amount of salts, which makes it unsuitable for a number of construction works. True, in countries where, apart from sea sand, there are no other types of it, the material is washed with fresh water, but this only increases the cost of the final product. However, sea sand is used quite often in construction, although not in the same way as other types of sand.
Pebbles, sand and crushed stone are indispensable assistants in the construction of all kinds of objects and structures. The correct choice of material for construction is the key to a durable structure or structure. Saving on the quality of sand can result in huge expenses for repairs in the future after cracks or damage occur.
Pay attention to the cost of sand - with delivery per cubic meter or not. The main part of the cost is delivery; do not forget also that it is more profitable to order a large batch of sand than to buy a couple of cubes, each time increasing the cost of sand due to transportation costs.
