All about quartz sand

Volume weight of dry quartz sand according to GOST

The volumetric weight of sand in 1 m3 is somewhere among the indicators of 1500 to 2800 kilograms.

At the stage of use for work purposes, specialists should be interested in:

• specific gravity and volumetric weight of building sand, kg m3;
• particle strength;
• characteristics of its surface;
• graininess or particle shape;
• the possible resistance of the material, the mineral composition is also taken into account;
• expansion coefficient of volumetric as well as linear type;
• strength;
• how much the particles are worn;
• filtration coefficient;
• compaction factor.

During the design of the composition of the building mixture, it is worth knowing:

• specific gravity of sand and volumetric bulk parameters of sand;
• the presence of voids and the ability to accumulate moisture.

Specific gravity

The specific gravity of sand kg m3 or specific gravity is an indicator that can be placed on a volumetric scale.

In almost all calculations for sand, only volumes of 1 cubic meter are used.

Application

Sand from rivers is applicable everywhere, both in construction, industry, and in everyday life. Construction sand is a good aggregate for floor screed, a compound of cement mixtures for masonry, plaster, concrete production, when arranging the foundations of buildings, pedestrian paths and paving stones, making drainage, etc.

In concrete

It is also a good material that absorbs noise. The usual sand is yellow, but this is not always the case. For example, in Hawaii, beaches are often covered with this green free-flowing material, in the Bahamas, pink shades of it prevail, and Iceland surprises with dark colors.

Due to the fact that it has great hygroscopicity, its layer, laid under the bottom of the asphalt, firmly holds it.

Road construction

Sand is also used as a purifier, because it removes various harmful impurities from the water well. That is why it is widely used in treatment plants.

As for domestic use, it is widely used by designers who, with the help of this golden free-flowing substance, bring to life their most creative ideas in the arrangement of the landscape.

Landscaping

It is also useful for gardeners and gardeners. They use it to make the soil in their areas lighter and more crumbly.

Main components in glass production

The properties and characteristics of any material are betrayed by those elements that make up its composition. The charge for glass melting includes the following required types of ingredients:

• basic element;
• oxides of various metals of the alkali group;
• substances that are responsible for certain properties;
• auxiliary components.

Quartz sand

The main element in the manufacture of glass is quartz sand or silicon oxide. This component is widespread. It is mined in an open way. Therefore, the cost of silica is relatively low. On average, the market price for 1 ton of treated quartz sand is in the range of 3-4 thousand rubles.

The processing of this component means its purification from various impurities and crushing to the desired fraction. Usually, a particle size of 0.1–0.6 mm is used for the charge. After that, the sand mixture is packed in bags of 25 or 1000 kg and sent to glass production. The main advantages of quartz sand include:

• resistance to chemical reactions;
• immunity to physical influences;
• high flowability, which increases the dosing accuracy.

Sand mixture (PS) for glass production consists of the following components:

• silica (over 95%);
• iron oxide (up to 0.25%);
• aluminum oxide (up to 4%);
• moisture (no more than 0.5%).

According to GOST 22551-77, grades of quartz sand are distinguished depending on which glass products the sand mixture will be used for:

• OVS (especially responsible ones with high translucency);
• OBC (responsible with high translucency);
• Sun (with high transparency);
• C (translucent);
• B (colorless);
• PB (semi-white);
• PS (with reduced translucency);
• T (dark).

In the designation of PS grades, after the letters of the above abbreviations, three numbers are indicated, which show the mass fraction of iron oxide in thousandths. And the following letter "B" or a number means the grade of the mixture. So, the name of the brand OOVS-010-B says that this premium grade PS is intended for particularly critical products with high translucency. It contains 0.01% iron oxide.

Calcium oxide

CaO hardens the glass and increases its chemical resistance. This component is about 10% in the entire charge mixture. It greatly facilitates the melting process and brightens the glass melt.

Calcium oxide is added in the form of limestone, which is composed of calcium carbonate. This rock is white or gray in color. Dolomite is also used as a source of CaO in glass production. This natural material additionally contains magnesium oxide, which reduces the rate of crystallization of the mixture during cooking.

Limestone and dolomite rocks must contain less than 0.2% iron oxide. At the same time, the first element should contain more than half of CaO, and the second, more than 30%. Rocks are delivered to glass production in the form of lumps and stones. There they are to be crushed. And already as lime or dolomite flour they enter the charge. The price varies from 8 to 10 thousand rubles per ton.

Potash soda

This element, interacting with other components, reduces the glass melting point, thereby speeding up the technological process. Potassium oxide not only helps to clarify the molten glass, which entails an improvement in light transmission. But it also gives firmness to the finished product.

In order to obtain potash soda when smelting glass, potash or potassium carbonate is added to the charge. It includes:

• potassium oxide (almost 70%);
• carbon dioxide (about 30%).

During smelting, the first element takes part in glass formation, and the second volatilizes. Potassium oxide is responsible for the shine of glass, gives it a unique shade. Therefore, the substance is used in the production of crystal and optics. To obtain sheet glass, it is rarely added. Potash is of two types:

• crystal;
• calcined.

For the production of glass, the second type is used, which contains more than 98% potassium carbonate. It is a yellow powder that quickly absorbs moisture. Potash, artificially obtained from minerals containing potassium chloride and double magnesium-potassium carbonate, is an expensive material. And little is used in the production of glass.

It is much cheaper to use a soda-potash mixture, which includes potassium and sodium oxides. In addition, with this option, two ingredients are introduced into the charge at once.

Application

This inorganic mineral has a number of properties that make it a number of unique materials. Quartz sand:

• does not react with other chemicals;
• has a high bulk density;
• durable (the grains are almost not subject to abrasion);
• radiation safe;
• is a good sorbent;
• may be stained.

Due to its characteristics, the mineral has become a necessary material in many areas. How is quartz sand used? It is used in:

• light and heavy industry (fractional sand is filled with high quality building mixtures. It is one of the components of the self-leveling floor, decorative plasters);
• metallurgy (molding sand is involved in the creation of molds for casting. The resulting products have refractory properties, are distinguished by high strength);
• glass production (participates in the manufacture of glass containers, fiberglass, other materials. Magnetic cleaning removes the material from iron impurities);
• construction (participates in the creation of silicate bricks, concrete with refractory properties);
• housing and communal services;
• transport services;
• water purification (included in the filters, due to its absorbent characteristics);
• livestock (added to feed);
• production of composite electrical fuses (used due to dielectric properties).

Classification

So, according to the place of origin, it is customary to classify sand into the following types:

River sand

River sand is mined from the bottom of the rivers. It is distinguished by its natural purity and good culverts. The size of grains of sand in river sand ranges from 0.3 to 0.5 mm.

This type is used for the preparation of concrete mortars, cement screeds, treatment filters, drainage structures. It is worth noting that when preparing a concrete mixture, this type of sand precipitates quickly, so the solution must be constantly mixed. The cost of river sand ranges from 600 to 800 rubles per 1 m3.

Quarry sand

Quite logically, quarry sand is mined by the open method and includes impurities: dust-like particles, stones. The grains of open-pit sand are much smaller than that of river sand, ranging in size from 0.6 to 3.2 mm.

In its original untreated form, the building material can be used for trenching or as foundation sprinkling. Usually the leading manufacturers wash and sift the quarry sand. In this case, it can be used when performing plastering and finishing works, to create an asphalt concrete mixture, to form a screed.

Sea sand

This non-metallic mineral is extracted from the seabed using hydraulic shells. There are practically no foreign impurities in it, and salt participates in the purification.

This type of sand is considered the most demanded. It is used everywhere, from the creation of concrete structures to the formation of finely dispersed dry mixes. But, despite the unique characteristics of this building material, there is a shortage in it, since it cannot be mass produced.

Sometimes construction sand is considered a separate species. But, as a rule, it means both river and quarry sand. River sand can be of two colors - yellow and gray, and quarry - brown and yellow.

But it turns out that in nature there is also black sand, which shines like metal. It can be found in different parts of the world. And this type of sand is formed as a result of geological processes.

This mineral is composed of dark colored heavy minerals and is formed by washing out light constituents. The main minerals are magnetite, ilmenite, hematite.

Such sands are characterized by high radioactivity - 50-300 microroentgens per hour, but sometimes this parameter can reach a thousand microroentgens per hour. Due to its high radioactivity, this mineral is not used in construction and economic activities.

Artificial sand

It is worth noting that the above types of sand are natural, as they were formed by natural destruction of rocks. But, there is also artificial sand on the market, created by crushing marble, limestone, granite.

The most popular among artificial types of sand is quartz. It is made by grinding and dispersing the white quartz mineral until a homogeneous fraction is obtained. It differs from natural types of sand in that it does not contain impurities and has a homogeneous composition. These advantages make it possible to accurately calculate the parameters of a structure made on quartz sand.

It has found its application in the creation of decorative and finishing, welding materials. It is also used in the production of concrete, but rarely.

What it is?

The most common rock on the surface of our planet is quartz - scientists have found that up to 60% of the entire earth's crust contains quartz sand fractions. This rock is of magmatic origin, and its main component is silicon dioxide, which we used to call quartz. The chemical formula looks like SiO2 and is composed of Si (silicon) and oxygen oxide. In addition to these main components, the composition may additionally include oxides of iron or other metals, an impurity of clay. Natural natural mountain sand contains at least 92-95% pure quartz, it is used in construction and industry because of its high adsorption capacity and resistance to mechanical stress. Quartz is added to compositions for various purposes in order to increase the adhesiveness and increase the temperature resistance.

Silicon dioxide is a product that is obtained by grinding granite rocks. Sand can be formed naturally in nature, or it is obtained by artificial processing of larger fractions.

The finest fraction of quartz sand is 0.05 mm. Outwardly, the composition is similar to finely dispersed dust. The largest is considered sand, the size of the fraction of which reaches 3 mm. The most highly valued material has a translucent or whitish color, which is an indicator of its high silicon content. If there are any additional impurities in the sand, it changes its color palette.

In appearance, sand grains can be round or cuboid, with rough uneven corners, which are obtained by artificial crushing of granite rock, but such crushed chips have low efficiency and are not suitable for industrial and construction needs. There are standards for quartz sand, which should contain no more than 10% water, and impurities should not exceed 1%. Such a composition is considered to be of the highest quality, but it is not required everywhere.

The value of measuring the density of river sand in an unconsolidated state

Why is it so important to determine this indicator before the future construction of real estate? It is he who is able to display the real amount of materials in a single volume - a cubic meter. Thanks to him, you can use the material in terms of the ratio of spent resources and functionality.

After making the necessary calculations, you can calculate an approximate budget for future construction.

The building material considered in the article is subject to the norms of a separate GOST 8735-88, and this indicates:

• material with such indicators has fully passed the compliance with construction technologies;
• the properties of the material during work and after the construction of the house are quite predictable;
• a method to determine the mass of a material in a unit of its volume, tested and approved as a reference, allowing you to get the long-awaited and truthful result;
• During the material verification phase, only approved methods and technical recommendations were used.

You should remember that when purchasing river sand, its bulk density will be equal to 1600 kg / m3, which fully meets the construction standards. In addition, this material can be stored for a long time, it does not accumulate moisture, and lumps and voids do not form in it over time.

This indicator is critically important for many non-ore elements. To clarify this indicator in a specific batch of material, the manufacturer uses correction values. These numbers make it possible to determine the values ​​from the technological and economic point of view.

During the acquisition of a large batch, the coefficient allows you to level out deviations that are caused by the spread of indicators.For example, at the stage of purchasing ten tons of material, the amendment will allow determining the amount of material up to 2 tons per batch.

Views

Here are the main types of sands that are used in construction.

River - without impurities and clay

The river sand is of natural origin. It is most often used in construction. Also, an important property is its composition, in which there are no foreign impurities, such as clay or organic materials.

River

Usually has a gray or yellowish tint. River sand is considered the cleanest, in contrast to quarry sand. It is extracted from riverbeds, but it requires serious expenses and technical support. Hence the high cost of the material.

Career

Quarry sand differs primarily in composition, because it contains a number of unnecessary impurities, such as clay, organic matter, dust, quartz crystals and requires additional cleaning from them.

Career

If you use uncleaned quarry sand, then the finished structure can be seriously damaged, since the impurities contained in the sand can have serious negative consequences.

Artificial

Artificial sand.

Artificial

The name speaks for itself; it does not exist in nature. It is made from crushing various minerals:

slag;

Slag

granite;

Granite

marble;

Marble

limestone.

Limestone

This heavy sand is used only for finishing the walls of a building or floor screed, or in decorative solutions.

Quartz

Quartz sand is rarely used in construction work and is an artificially created material. Its main plus is in the complete absence of foreign impurities, because it is produced by grinding white quartz crystals.

Quartz

It is especially effective to use this type of sand in the creation of filters because its main property is its high dirt holding capacity.

Other calculation methods

Calculations must necessarily be carried out during the preparation of a planning project for all work on the construction of real estate. If the soil is loose, this will allow the pit method to be applied.

For this, the soil is leveled and a small pit is made, the displaced sand is transferred to a special container, which will be weighed later. A cone is placed over the pit; it must be covered with dry sand. Then the volume of the pit is determined, from which the volume of suspended sand is calculated. You also need to know the soil compaction coefficient and the sand filtration coefficient.

This method is quite simple, but only preliminary calculations can be obtained with it, so always check the results mathematically.

This parameter is assessed based on how the material can absorb and scatter radiation.

Average additional indicators of sand that is mined from quarries:

• first class radioactivity;
• density in an unconsolidated state - 1.4 t / m3;
• mass of particles per unit of their volume - 2.6 g / cm3;
• crushed rock content - 1.9%;
• heat capacity.

Average additional features that are mined from the river bottom:

• the ability of atoms of some isotopes to spontaneously decay, emitting radiation A (47 BK / kg);
• density in an unconsolidated state - 1.4 ± 0.1 t / m3;
• the amount of chemical elements that have passed into the composition of the alloy in the process of its production as a technological additive is 0.1%.

The number of voids should be determined by the density of the material in the unconsolidated state. On their own, this value can be measured in this way: a little sample material is poured into a measuring liter container and weighed.

If the material has accumulated moisture very strongly, then the sample can be placed in a ten-liter container, then the values ​​are converted to the required value.

From sand, which contains a high percentage of clay, it is forbidden to make plaster, high-quality building mixture, various mortars for construction.

With a high percentage of clay

All this is due to low frost resistance and strength.

Forming and casting. Application of quartz sand

Quartz sand is widely used in the production of molding sands for molds and cores in the iron foundry, steel and other metallurgical industries. Molding mixtures based on quartz sand must have certain properties:

• silica content (SiO2) up to 98%,

• the minimum percentage of impurities of alkali and metal oxides,

• clearly normalized percentage of clay impurities (depending on the brand of molding sand),

• rounded sand shape.

Molding sand from the group of companies "Khokholsky sand pit" grades 5K₃O₄03.5K₃O₃025 and 1T₁O₃02-03 enriched molding sands of fractions 0.1-0.4; 0.16-0.63; 0.16-0.8; 0,63-1,0 meet all the standards and requirements of GOST 2138-91 "Molding sands" The presence of certain grades of molding sands, check with our consultants.

Currently, the issue of supply and launch of equipment for the beneficiation of sands to grades 1K2O303, 1K2O2025 and 1K2O202 is being considered.

Quality quartz molding sand

This type of sand is mined in an open way. In addition to quartz grains, sand contains particles of clay, various minerals, mica, iron oxides, and feldspars. In places of extraction, the sand is enriched, freeing it from foreign impurities, which increases the quality and value of the foundry sand. Then the sand is divided into fractions according to the grain size.

Foundry sands are used as a refractory material in foundries in the manufacture of casting molds and cores, and are also the main constituent material for the preparation of cement, bentonite, synthetic resin and others.

The choice of high-quality, enriched foundry sand makes it possible to save on expensive binder material and at the same time ensure the necessary physical and mechanical properties of the mixtures.

The main qualitative indicator of the chemical composition of foundry sands is the content of silica SiO₂... The higher the amount, the higher the quality of the sand.

The peculiarity of quartz grains is that they are very hard, have great refractoriness and transparency.

That is why quartz sands are light in color. Various color shades are imparted to the molding sand by impurities. The less impurities are contained in the sand, the lighter it is and the higher its refractory properties.

Depending on the content of silica, clay component, and harmful impurities in accordance with GOST 2138-91 “Molding sands. General technical conditions ”distinguish several classes of molding sands: enriched (Ob1K, Ob2K, Ob3K), quartz (1K, 2K, 3K, 4K), semi-bold (P), oily (F), very fat (OZh).

The fractional composition of sand is determined by sieving through a set of sieves with mesh sizes ranging from 2.5 to 0.005 mm. The remainder of the sand, located on three adjacent sieves, is called the main sand fraction. Its content should not be less than 70%.

By grain size, quartz foundry sands are classified into the following groups:

Foundry sand categories

According to the distribution of the main fractions of sand on three adjacent sieves, there are two categories of sands: A and B. Category A includes sands with the remains of the main fraction on the uppermost sieve, greater than on the extreme lower sieve; to category B - sands with the remainder of the main fraction on the extreme lower sieve, more than on the extreme upper one.

In the marking of sand, the class designation is in the first place, the grain group is in the second, and the category is in the third. For example, marking about 1K02A means: enriched quartz sand of enrichment class 1K of grain group 0.2 of category A.

MOLDING SANDS

Choice

The choice of this or that type of sand is determined by its purpose, economic feasibility.For example, river sand is more suitable for making concrete. The material does not require thorough rinsing. Provides resistance to moisture, temperature extremes. However, it should be understood that determining the type of bulk substance is not enough to obtain the desired result.

In this case, it is also important to pay attention to the concrete grade. For each brand, there are acceptable grain size indicators. For example, for concrete grade M200 and below, fractions from 1 to 2.5 are suitable.

For grades M350 and higher, fractions from 2.5 to 3.5 are suitable. When laying the foundation, fractions from 1.5 to 3.5 are used

For example, for concrete grade M200 and below, fractions from 1 to 2.5 are suitable. For grades M350 and higher, fractions from 2.5 to 3.5 are suitable. When laying the foundation, fractions from 1.5 to 3.5 are used.

Quarry sand can also be used, but only after thorough washing. As a rule, it is used in order to save money when there are no high requirements for the result. Due to the presence of a large amount of additional impurities, the material is not able to provide sufficient structural strength. Therefore, it can only be selected if heavy loads are not expected.

Quartz or gravelly types of material are obtained artificially. This requires significant financial, labor and time costs, therefore, from an economic point of view, it is unprofitable. This type of sand is often preferred in landscape design. This is due to the uniformity, evenness of the surface of the grains.

For any finishing work, production of industrial mixtures, brickwork, tiles, it is recommended to choose a material with a minimum amount of impurities. River sand is suitable for this. The use of a quarry type of material is allowed in industrial production or where there are no strict requirements for the strength and stability of the final product.

When choosing sand on your own, you should carefully study the composition, characteristics, compatibility with other components of the mixture.