Gravel is understood as a sedimentary rock of inorganic origin, consisting of rolled pieces of minerals and rocks. This natural material, formed by the weathering and erosion that occurs in rocks. Particle size different types gravel can be from 1 mm to several centimeters.

Typically, deposits are found on river terraces, floodplains, in glacial deposits, and coastal coastal zones. The formation of this material is associated with the activity of rivers, seas, and glaciers.

Depending on its origin, gravel can be river, sea, mountain, or glacial. The formation of river and sea gravel (pebbles) is associated with the impact flowing water. On the coasts of the seas it is formed due to the action of waves, ebbs and flows. The resulting friction of pebbles against sand particles, as well as against each other, plus the grinding effect of water flows lead to the fact that over time they acquire a rounded shape and smooth surface.

Mountain gravel is formed during the natural destruction of rocks under the influence of wind, rain, air temperature fluctuations, and cycles of freezing and thawing of water. It consists of pieces of rock of various shapes and has a rough surface.

Mountain gravel

The glacial variety is associated with the movement of glaciers. This process is still happening in some places, but in the past, during the spread of glaciations, it was observed in many areas.

Particles of river and sea gravel can be representatives of completely different rocks and minerals, so they have different color And different properties. If the mother breed was different greater strength, then the gravel particle will be harder and less rolled.

Among the grains of gravel, it is impossible to detect halite (sodium chloride mineral) and other rocks and minerals that are highly soluble in water, which will simply be washed away by water flows.

A close analogue of gravel, but only with a smaller particle size, is sand.

Properties of gravel

fine gravel

1. Based on particle size, fine gravel (1 – 2.5 mm), medium gravel (2.5 – 5 mm) and coarse gravel (more than 5 mm) are distinguished, that is, small, medium and large fractions. Depending on the size of the fraction, the bulk density of the material also changes. If the gravel is small, then it is 1700 kg/m3, and for coarse gravel it is 1500 kg/m3.
2. Hardness and strength. Determined by the degree of abrasion and crushability. They depend on the composition of the particles and have highest value when using this material in road construction.
3. Temperature stability. Depends on how much freezing and freezing the particles can withstand.
4. Amount of impurities. The most common undesirables are clay and dust. The least amount of impurities is in gravel formed by water flows, and the largest amount is observed in the mountain variety of this material. Also considered undesirable are impurities such as gypsum, silica, pyrite, pieces of dense clay, and iron ore.
5. Predominant grain shape. It can be round, lamellar, rounded-angular and angular.
6. Washed gravel. It is obtained from ordinary gravel by thorough washing, and therefore, specific gravity There are minimal impurities in it.

How is gravel mined?

Gravel mining

Gravel extraction is carried out open method using special equipment. Gravel mined from mountain quarries needs to be washed. This material is transported various types ground transport. For short distances, conveyors and trolleys can be used.

Where is gravel used?

The availability and prevalence of this material makes its use widespread and ubiquitous. Main directions:

1. Concrete production.
2. Road construction.
3. As decorative material.

Mountain, glacial or mixed gravel is more suitable for making concrete. Due to the roughness of the particles, this material creates better adhesion to cement than smooth particles of water gravel. Another condition is the resistance of the particles to alkalis.

In road construction, the main requirement for a material is the strength of the particles. In some regions, frost resistance is also important.

Gravel is increasingly being used as a decorative material. Fine gravel is suitable for paths, mini beaches, and recreation areas. For this purpose it is optimal aquatic species gravel. Larger gravel has found application in the construction of artificial reservoirs and in creating landscapes on a personal plot.

Gravel and crushed stone

Gravel and crushed stone are quite similar materials in appearance, but they also have significant differences. Gravel is formed in natural conditions, and its particles have softer outlines. Crushed stone is obtained artificially - by crushing solid rock. Therefore, its particles have sharp outlines and sharp protrusions. Crushed stone gives stronger adhesion to cement, so the concrete produced from it has more high level strength. At the same time, a cubic meter of gravel will cost less than a cubic meter of crushed stone and is quite suitable for the construction of small structures.

Today this industry is actively developing National economy like construction. Every year, various construction and Decoration Materials. Any builder and even just the owner of a summer house or private house needs to know how this or that material differs. Everyone knows that crushed stone and gravel are widely used in construction. But not everyone knows how they differ from each other. In fact, there is a difference between them, and a significant one. The differences can be determined by eye. Crushed stone and gravel are substances formed from rocks, that is, they have the same origin. In addition, crushed stone and gravel are widely used in construction and are irreplaceable raw materials. By the way, on this site you can buy recycled crushed stone with delivery.

Gravel appears when rocks are broken down and has a smooth surface.

Almost every builder has had to deal with these rocks. Despite their similarity, including external ones, they have a number of fundamental differences, on which their scope of application largely depends. Let's take a closer look at how gravel differs from crushed stone. short description materials.

Gravel is a loose sedimentary rock containing fine particles minerals formed as a result of the natural destruction of hard rocks. It is classified into 3 types according to particle size: small (1-2.5 mm in size), medium (2.5-5 mm) and large (5-10 mm).

Industrial gravel is used in road construction and foundation laying.

Depending on its origin, gravel can be mountain, sea, river, lake or glacial. Sea and river minerals differ from mountain minerals: they have a smoother surface. All this contributes to the fact that when using them in construction work ah, the adhesion to the surface is several times less.

In the composition of this mineral one can often find various impurities, such as sand and soil. This impairs adhesion to concrete. The mountain type is used most widely in construction. It differs in that its surface is rougher. Its areas of application are as follows: expensive construction, backfilling sites, as a filler for heavy concrete, foundation construction, and so on. These stones also differ in their variety of colors: they can be pink, black, yellow, blue, brown.

Due to all this, they also differ in that they serve as good design raw materials, being used for decorating flower beds, arranging gardens and paths.

Distinctive features of crushed stone

Crushed stone is an inorganic raw material (stone) obtained by crushing rocks of granite, limestone and boulders. The difference between gravel and crushed stone is primarily observed in appearance: crushed stone has great roughness, very often sharp corners; In addition, it is larger in size. All this ensures good grip various surfaces

and materials. Crushed stone can be had various shapes and, thanks to this property, is actively used not only in construction, but also.

landscape design Depending on its size, the following types of mineral are distinguished. Up to 5 mm – granite screenings used for coating sports grounds , protecting roads from ice. The next option is crushed stone with a size of 5 to 10 mm. It is well suited for making floor slabs and concrete. The third type – sizes from 5 to 20 mm. It is used for pouring bridge structures, making concrete, foundations, bridges and roads. The next type is a mineral ranging in size from 20 to 40 mm. This is the middle faction. Ideally suited for the construction of roads, tram lines, preparation of concrete and reinforced concrete, construction of foundations for large buildings . Another fraction is 40-70 mm. Used for the construction of buildings, roads in populated areas

. This is a large faction. And crushed stone ranging in size from 70 to 120 mm - for decorative purposes.

Its very useful properties are frost resistance and strength. Based on frost resistance, it is divided into groups.

Differences between the two materials large sizes, better adhesion. All this ensures his high demand for Russian market. It is easy to confuse ordinary granite crushed stone with mountain gravel, since the difference between them is small. Both of them are inorganic, that is, their composition is very similar.

The difference between gravel is that it comes different types: sea, river and so on. It depends on it beneficial features and application. It largely has a smooth surface and rounded dimensions, which is widely used for decorating facades, roads, gardens, and the like. Big practical significance for the use of crushed stone, it has such a property as flatness: the more square the crushed stone is, the better it fills the voids.

Granite and crushed stone are similar Construction Materials, which, nevertheless, have characteristic features. Firstly, the difference between them is in appearance. If you look closely, you can see that the surface of the crushed stone is more uneven, has sharp corners, and is rough. This important property, on which the adhesion strength of the material to a particular structure depends. Gravel is smoother and rounder, so it is used to a limited extent for concrete preparation. Their origin is the same. Separately, it is necessary to highlight the so-called mountain gravel, which is similar to crushed stone.

Gravel has smaller particle fractions than crushed stone. The latter is classified into 6 groups depending on the size of the granules. Each of them is used in a specific area. Most in demand crushed stone of the middle fraction is used. Special attention you need to pay attention to the cost of both raw materials. It is approximately the same, but due to its smaller size, slightly more gravel is usually required, since it fills the voids better and thus is consumed faster. Properties such as radioactivity and strength are approximately the same.

Before listing the differences between crushed stone and gravel, it is necessary to define gravel.

What is gravel?

Gravel- these are rounded (rounded, with unclear edges) fragments of rocks formed as a result of the natural destruction of solid rocks. Those. gravel is a material created by nature .

Gravel can have different sizes (fractions): from small, slightly larger than grains of sand (5 mm), to very large, more than 70 mm (so-called boulders).

What is PGS?

In nature, gravel occurs along with sand. This mixture of sand and gravel is called a sand-gravel mixture, or SGP.

Sand and gravel mixture (SGM)

The rock, depending on the content of gravel and boulders in it (in % by weight), is divided into 3 types:
1) sandy rock (gravel - up to 10%, boulders - 0%);
2) sand and gravel rock (gravel - more than 10%, boulders - up to 5%);
3) boulder-gravel-sand rock (gravel - more than 10%, boulders - more than 5%).

To obtain gravel from such a rock, it is necessary to separate it from the sand. The gravel can then be sorted into the required fractions using a screening process (scattering through a set of sieves).

Since gravel is formed in nature as a result of the natural and prolonged destruction of rocks, it has many foreign inclusions, such as clay, grains of sand, particles organic matter etc. Therefore, to get more pure material The gravel must be washed with water. After this, you get clean washed gravel.

Washed gravel

Now let's move on to the differences between crushed stone and gravel.

What is crushed stone?

Crushed stone- This bulk material with grains larger than 5 mm, crushed rocks, gravel or boulders.

To obtain crushed stone from gravel or boulders, the source material is delivered to crushing and screening machines (mills, crushers and screens), where the gravel (boulders) is crushed. After this, the crushed stone obtained as a result of crushing is scattered into the required fractions using screens.

We get the first difference between crushed stone and gravel: crushed stone is a product of crushing. Those. crushed stone, unlike gravel, is not mined in nature in finished form, but is produced using crushing equipment.

According to GOST 8267-93 "Crushed stone and gravel from dense rocks for construction work", which is the main document regulating the quality requirements for these materials, crushed stone from gravel and boulders must contain crushed grains in an amount of at least 80% by weight . In this case, the grain is considered crushed if its surface is more than half broken.

The second difference between crushed stone and gravel is that crushed stone can be a product of crushing not only gravel or boulders, but also other rocks, for example, granite, diabase, limestone, etc. Crushed gravel is produced from gravel and boulders, crushed stone is produced from other rocks, which your physical and chemical properties may differ significantly from gravel.

Third difference What needs to be noted is the difference in the cost of materials. Because production technology crushed gravel Compared to the production of gravel, it additionally requires the use of crushing equipment, which is reflected in the rise in price of crushed stone. In this regard, gravel, as a rule, costs less than crushed stone. This can be exploited by unscrupulous suppliers who bring gravel under the guise of crushed stone, i.e. not crushed material, trying to get additional income on the price difference. Therefore, if you order crushed stone, be sure to check that the amount of crushed grains in it complies with GOST.

Another difference- This different sphere application of these materials. Since gravel has a more rounded shape, it is inferior to crushed stone in terms of adhesion characteristics to other materials. Crushed stone, due to its angular and rough surface, is used as a filler in concrete and asphalt concrete mixtures (it binds more firmly in them), as well as in road construction (it compacts better). Gravel is most often used in the construction of drainage systems, as well as as a decorative material in landscape design.

What is alluvial and seeded sand in construction?

How does crushed stone differ from gravel in origin and properties?

Bulk density of sand - technological and commercial significance Density of crushed stone for construction - features and nuances Sand for construction - types and characteristics Supply of washed and river sand in the Moscow region Places and methods of extracting granite crushed stone What is the convenience of sand in bags? Which backhoe loader should you choose to rent? Sand in bags of 50 kg. Advantages and disadvantages. Features of work on removal of soil dumps and construction waste Sand for road construction. Main selection criteria Sand for children's sandboxes Construction of a road made of crushed stone with a sand cushion What construction equipment to rent Choosing crushed stone for the blind area of ​​a house Drainage system on a site for a residential building Compaction coefficient of sand and crushed stone How to properly raise a plot of land? Rent a backhoe loader in Shchelkovo Rent a backhoe loader in Zelenograd Rent a leveling excavator in Moscow Pile cutter. What is it and how can I rent a pile cutter? Renting a front loader in the Moscow region Rent a backhoe loader in the Istra region What do you need to rent a dump truck without a driver? Hydraulic hammer. Technical specifications and rental in Moscow Rental of construction equipment in Dmitrov Rental of construction equipment in the Moscow region Advantages of renting GCB equipment Comparison of wheeled and crawler excavators Rental of special equipment in Shchelkovo Front loader. Description and characteristics Crushed stone frost resistance indicator Characteristics and varieties of granite crushed stone and screenings Classification and characteristics of river sand Properties of river sand Vessel classification Types and features of using natural gravel Properties, types and scope of application of black crushed stone

What is the difference between crushed stone and gravel in terms of origin and properties?

Materials obtained from rock, which are particulate matter of various sizes, in fact - fragments of stone of various origins, gravel and crushed stone have fundamental differences. The high value of these materials in the construction industry forces us to pay attention to their properties, which may largely depend on the origin, type of source rock, shape, size and strength characteristics of the grains.

Possibility of using crushed stone and gravel in construction practice, landscape design and road construction is determined by its composition, fraction size and flakiness index. The closer the grain shape is to cubic, the higher the value of the material for construction and concrete production.

For large construction projects related to the need to form concrete monolithic structures, crushed granite stone 20-40 with a flakiness index of 5 - 15% is suitable. For forming a foundation and pouring structures into individual construction Crushed stone of fraction 10-20 is used, and often, for reasons of economy, material of limestone origin is purchased.

Differences between crushed stone and gravel - main features

One of the most frequently asked questions- these are the differences between crushed stone and gravel, which determine their properties and possibilities of use.

These differences can be listed at clear example, imagining the grains of the material - most of the main features and characteristics are visible to the naked eye:

• the shape of the grain - gravel particles, exposed to natural influences for thousands of years, are always round, they are ground and polished by water, wind, sand rubbing against stones;
• the relative unity of the rock is characteristic of crushed stone, which is obtained by blasting and crushing mechanically rock masses;
• a sign of flakiness is the ratio of cubic, lamellar and needle-shaped particles in the massif, characteristic of crushed stone, the quality of which increases with the increase in the number of cubic grains;
• mining path - gravel represents the result natural process, crushed stone is a product of industrial destruction and grinding of the original rock.

The main indicator that makes up the value of crushed stone in construction practice associated with concrete is the shape of the grain. Granite crushed stone of low flakiness consists of 85 - 95% cubes. In such an array there are few particles in the form of plates or pointed fragments, which do not give a predictable effect high density when filling a concrete monolith.

The use of crushed stone in construction practice

Crushed stone extracted from “ torn stone” rocks destroyed by explosion may have different composition. The greatest construction value is made of granite and basalt materials. These are rocks of volcanic origin that have maximum strength and minimum water permeability. Accordingly, they have high frost resistance - as a rule, granite and basalt crushed stone can easily withstand up to 350 freezing cycles.

Limestone crushed stone is of sedimentary origin, and therefore less durable. Its properties make it possible to use medium and large fractions in construction if the project does not provide for significant loads on the foundation and concrete wall monoliths. Small fractions are suitable for filling roads and sites, but with a limited weight load and throughput. For the construction and formation of powerful bulk foundations, it makes sense to buy crushed stone 40 - 70, and for use in a monolith foundation light structure- fractions 10-20 and 20-40 of crushed stone of sedimentary origin.

Gravel - applications and properties

Gravel mined in quarries is the result of the destruction of rock or sedimentary rock during water, wind or sand erosion, natural destruction and grinding of the original rock. Gravel deposits are usually located in existing or dry reservoirs, where the flow of water has brought ground, naturally rounded stones for thousands of years.

During the extraction and processing of gravel, it is divided into fractions, passing sequentially through sieves with different mesh sizes. The sizes of fractions within one deposit differ slightly, as does the composition of the massif, which is usually distinguished as mountain lake, sea, glacial and river. The more grains spend in flowing water, the more rounded their shape will be.

Gravel stone can have high strength if the source rock is granite, basalt, feldspars and other volcanic emissions. An indicator of strength is the level of abrasion of grains placed in a drum with metal balls that rotate during testing.

The sizes of fractions and other characteristics of the gravel massif are determined according to the standards of GOST 8269.0-97. To save money, mixing different fractions is allowed if gravel is used in decorative purposes, where its strength and packing density will not affect quality characteristics buildings or foundations. The use of gravel in the formation of concrete monoliths is undesirable - its grains without edges cannot create an internal structure that gives the concrete casting the required strength.

Depending on the type of material, the frost resistance of gravel can reach 400 cycles, but the flakiness indicator is practically inapplicable to it - the shape of the grains is very diverse.

Difference in cost of gravel and crushed stone

The price of crushed stone per 1 m3 reflects the whole range of its properties, advantages and possibilities of use. It also takes into account a rather expensive mining process, in which rocks are initially torn apart by explosions, then large fragments are moved for crushing, and only then they are screened, divided into fractions and determined by flakiness and strength.

In modern project construction granite crushed stone filler is used in the composition concrete mortar, and the material in its pure form is used to create drainage bases and cushions. Small fractions are actively used in the creation road surface. In some cases, the use of crushed concrete of secondary origin and gravel stone is allowed, but as a rule, such foundations and drainages are not designed for high strength and heavy weight designs.

These two materials are so similar in appearance that it is not always possible to distinguish them visually. To find out how gravel differs from crushed stone, let’s look at what they are and how they are characterized.

Both are of natural origin, but the second is formed as a result of the destruction of rocks and, according to its location, is called lake, river, sea, mountain and glacial. It is obtained by sifting its natural mixtures with sand.

Crushed stone, unlike gravel, is produced by artificial crushing and sieving:

1. mountain hard rocks, boulders, pebbles;
2. waste from processing plants, asbestos production, ferrous and non-ferrous metals mining;
3. slag from blast furnace and chemical production;
4. construction waste(concrete, bricks and asphalt) and is called secondary.

The fractions of crushed stone and gravel can be very different, but the former is found with larger grains:

• from 0 to 5 mm - granite screening, it is sprinkled on sports and children's playgrounds, roads during icy conditions, and is also an excellent decorative finishing stone;
• 2-5, 5-10, 5-20, 10-20 – fine-grained, finds wide application when pouring foundations, manufacturing floor slabs, reinforced concrete products, in landscape design;
• medium-fraction (grain size - 20-40) is indispensable for mixing concrete, in the construction of foundations, roads, bridges and tram tracks;
• coarse-grained (25-60 and 40-70) are in demand in the construction of railways and roads, in the manufacture of all kinds of reinforced concrete structures;
• rubble stone (40-200) is used for the construction of buildings, as decorative rock- for decoration artificial reservoirs, pools, borders.

Distinctive features of materials

Gravel differs from crushed stone in size; it is divided into: small with grain sizes of 1-2.5 mm, medium-fraction - 2.5-5 and coarse-fraction - 5-10. River and sea have a rounded, smooth surface, mountain - more textured, which contributes to better adhesion to sand-cement mortar. This determines its widespread use as an excellent aggregate for mixing heavy concrete, when pouring foundations, backfilling platforms and foundations, and in road construction. Going into production roofing materials. Medium-fraction is used in filtration plants for primary water treatment.

The grains have quite a variety color scheme(pink, yellow, white, black, gray-blue, brown) and tend to change color with changes in light and humidity, therefore they are actively used for decorating facades, in landscape design - when arranging paths, platforms, alpine slides, flower beds, swimming pools and artificial reservoirs.

Basic distinctive features gravel and crushed stone:

• the second has larger grains;
• complex cuboid or needle-like shape and torn texture;
• much greater adhesion to bases and building materials, for example, with sand-cement mortar, which leads to its primary use in the construction of foundations, roads, and railway embankments.

You can often hear the question: “What is the difference between gravel and crushed gravel?” The difference lies in the methods of obtaining them. The first is obtained during the natural destruction of rocks and accumulates at the foot of the mountains in a mixture with sand. Also contains dust, soil, clay. But the second one is produced by artificially crushing boulders.

Price

The table shows average prices in Moscow

Name	Price RUB/m3, including VAT 18%	Price rub/m3 from 15 to 300 m3	Price RUR/m3from 300 m3
Gravel 5-20		from 1 400	from 1 380
20-40		from 1 380	from 1 360
40-70		from 1 380	from 1 360
Crushed granite 2-5	2 400
3-10	2 100
5-20	1 850
20-40	1 750
25-60	1 750
40-70	1 750
gravel 5-20	1 650
20-40	1 600
limestone 5-20	1 350
20-40	1 300
40-70	1 350
secondary made of concrete 20-40	800
40-70	780