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.
Gravel appears during the destruction of rocks and has 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.
Characteristics of gravel
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 finishing 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, it is actively used not only in construction, but also in landscape design. Depending on its size, the following types of mineral are distinguished. Up to 5 mm - 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 There is a difference between gravel and crushed stone, but it is not noticeable at first glance. Their similarity is that they are formed from rocks and have the same origin. Both materials are widely used in construction. The similarity can also be traced externally. They may be the same color. Crushed stone has a more uneven surface,, 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 it has such a property as flatness: the more square the crushed stone, the better it fills the voids.
Both crushed stone and gravel are often used in the construction or renovation process. At first glance, these bulk materials are very similar and have no significant differences; they can be interchangeable. But in fact, the difference between crushed stone and gravel is significant. And therefore, when solving issues related to construction, it is imperative to know and take into account the main differences between these materials.
General properties of crushed stone and gravel
Origin
Both crushed stone and gravel are bulk building materials consisting of grains (pieces of rock) different sizes. One of the common properties is natural origin. But if crushed stone is obtained by crushing only rock (with the exception of artificial crushed stone), then gravel can also be river or sea gravel.
Application area
Today crushed stone and gravel - popular materials in construction. They are used for:
- leveling areas;
- reinforced concrete structures;
- concrete pours;
- facade finishing;
- laying out paths, etc.
Difference between crushed stone and gravel
Production technology
Crushed stone is produced by crushing rock fragments using stationary or mobile equipment (screens, mills). Then the building material is sorted into fractions. You can learn more about the technology of mining and processing of rock.
Gravel is formed naturally during the gradual destruction of rock. The grains are collected on the surface using special equipment. Typically, such building material contains many impurities - sand, clay, soil, various organic matter. Therefore, stones can be subject to additional processing: calibration, screening, washing. And if the gravel is very coarse, it can be crushed. Like crushed stone, gravel is also sorted into fractions.
So, gravel is formed as a result of the independent destruction of rock, and crushed stone is formed as a result of mechanical destruction.
Shape and surface properties
Crushed stone grains have an arbitrary shape with sharp corners: it is this property that ensures good adhesion of crushed stone.
Beautiful appearance gravel - its main advantage: the grains are round and flat.
The difference between crushed stone and gravel is also that while the grains of the first material are rough, the grains of the second have a smooth surface.
The shape of the grains determines where it will be used. bulk material. Crushed stone has better technical characteristics (compared to gravel): this ensures reliable adhesion to other building materials. It is good to use as an additive to concrete or reinforced concrete mortars: it will give the structure strength and durability. If necessary, you can familiarize yourself with it in detail.
Gravel has more beautiful shape grains, therefore most often used in decorative purposes: it is used to decorate paths, house facades, and is used in landscaping and gardening areas, but rarely for making concrete and building foundations.
Color spectrum
Crushed stone does not have the same variety of colors as gravel. As a rule, this is a single-color material. Gravel can be pink, brown, blue. This characteristic (as well as the shape of the grains) also determines the use of gravel for decorating landscapes.
Price
The price of gravel and crushed stone is approximately the same. But during the construction process, gravel is consumed faster than crushed stone, so much more of this material will be required. This is due to the fact that rounded gravel grains quickly fill voids.
Before you buy bulk material, determine what construction tasks you need it to solve, and also thoroughly study the main differences between gravel and crushed stone.
What is the difference between gravel and granite crushed stone?
Many builders wonder what crushed stone would be better suited for production of equipment. After all, there are several types of material. Not everyone knows the difference between gravel and granite crushed stone.
What is crushed gravel?
Crushed gravel is produced by crushing gravel rock. Its strength has high indicators, due to this it is in great demand in construction, indispensable in the construction of houses, public utilities, civil engineering, construction of structures for which the level of background radiation is important.
Today, purchasing this crushed stone is not difficult. Before purchasing, you should decide on the size of the stones. Crushed gravel is divided into three types of fractions:
- 5-10 mm is the most common size. Used for the production of reinforced concrete structures and others;
- mm - in demand for the production of high-strength concrete products;
- 40-70 mm - close-up view, has high strength and durability. Suitable for large, voluminous buildings, repair work, railway embankments. Perfectly and reliably strengthens concrete structures, foundations, and various structures.
Description of granite crushed stone
It is also produced by crushing or exploding granite, which is blown on a special machine, distributed into fractions, passes state standards and only then goes on sale. It has high levels of water resistance, frost resistance, and strength. The structure of granite consists of mica, quartz, and spar. This composition ideally resists temperature changes. This crushed stone happens different colors: green, gray, red, dark blue, which allows it to decorate any yard, garden, pool, park, carrying out finishing work.
As for the fractions of granite crushed stone, they are more diverse than that of gravel. For example: from 5 to 20 mm are well suited for laying routes, bridges, and durable concrete; from 20 to 40 mm are popular for various construction works; from 25 to 60 mm are ideal for embankments of railway and tram tracks, areas for parking heavy cargo and equipment; from 40 to 70 mm representative of large stones, which are regularly used in industrial use and large buildings; the largest type from 70 to 300 mm is used for landscape design and massive foundation structures.
As for flakiness, it has a small percentage. This means that most of the components of granite crushed stone are cube-shaped, and it is very popular.
Advice: From all of the above, it is concluded that both types of crushed stone are good in their own way, but still granite has a little best qualities than gravel. The first type is durable, less prone to cracks, and cuboid stones increase its serviceability. This material is environmentally friendly and does not pollute environment. The second option is less durable, but has a first class radioactive background and excellent frost resistance.
Finishing, filling, decorative paths, drainage, concrete pours, reinforced concrete structures– all these and other construction works are impossible without gravel and crushed stone. However, to a person far from production environment, the fundamental differences between these materials are not noticeable at first, superficial glance: both are almost identical in appearance, both are used for approximately the same list of works, both relate to dense rocks. However, in reality, crushed stone and gravel are two different building materials, each with its own characteristic features and differences.
What are crushed stone and gravel?
Both crushed stone and gravel are relatively small pieces of rock whose main purpose is construction. The diameter of individual stones can be very different - from 5 to 200 mm, while the grain size is dictated technological requirements to ongoing construction work. The main difference between crushed stone and gravel is the shape. Crushed stone has sharp, rough edges, while gravel has much more rounded shapes. It is the shape that affects the difference in application: crushed stone is ideal for use in concrete and reinforced concrete solutions, while gravel is better suited for decorative purposes.
Production of crushed stone and gravel
Natural gravel is loose, loose fragments of various dense rocks, having a sloping, rounded shape with vaguely defined edges. Gravel is formed only in natural conditions , in the process of natural, temporary destruction of the rock. According to GOST, gravel can have different sizes - from 5 to 80 mm, and larger gravel is crushed into crushed stone.
According to geological characteristics, gravel is divided into several subspecies - river, sea, glacial and mountain. Gravel has the most streamlined shapes water resources- river and sea, which is why its construction value is lower than that of the other two types. Rounded edges have a very low degree of adhesion to other substances, in particular with concrete mixtures, therefore in the production of concrete and reinforced concrete products it is preferable to use glacial and mountain gravel.
In fact, gravel mining is the collection of scattered stones lying on the surface using special equipment. In the future, if necessary, the stones undergo additional processing - calibration, screening, washing. The resulting material, which is relatively homogeneous in composition, is called gravel.
Since gravel is formed during the destruction of rocks, it contains a very high content of various debris - sand, clay, particles of organic substances, and so on. Therefore, the processing of natural gravel includes not only sorting into fractions, but also screening, and sometimes washing - this allows you to get rid of sedimentary impurities.
Natural gravel contains a wide variety of rocks and minerals. Because of this feature, the assessment of strength and resistance to temperature changes must be made on the basis of several samples, with the obligatory inclusion of the weakest, easily destructible grains.
Crushed stone is also a derivative of the destruction of rocks, but, unlike gravel, the destruction is carried out intentionally. Often, crushed stone is formed during stripping operations as a by-product, and is also a consequence of mining and processing operations.
In the production of crushed stone, several types of crushing machines are used, the type and type of which is determined required quality final product. Crushing equipment can be either stationary or mobile, depending on the deposits of natural material.
The first stage of crushed stone extraction– in the case when its production is not concomitant – it is a rock explosion. Blasting specialists make a hole in the rock mass into which explosives are placed. After detonating the charge, engineers determine whether the resulting debris is of sufficient size. If necessary, large blocks are undermined again. Then, using special equipment, the stone fragments are delivered to the installation site of crushing equipment. Special screens and mills – crushing and screening machines – crush stones to required size. The fraction or size of the grain - an individual pebble in the crushed stone mass - is determined technological features those works for which crushed stone is intended.
During mining and processing operations, the production of crushed stone looks a little different. Here, the main stage of production is sifting of the enriched rocks, during which crushed stone is selected. This is exactly what the rock will be, which does not contain mined substances, the so-called empty rock, that is, it is a by-product during the development of the field. This kind of crushed stone production is less common than traditional blasting.
Main characteristics of crushed stone
Crushed stone is widely used in construction - in the preparation of concrete forms and mortars, in road laying, in the production of asphalt and bitumen, in finishing and decorative works and so on. Of course, for the right choice relevant material you need to know the basic specifications crushed stone And, perhaps, the main one is the faction.
Fraction
Fraction is the grain size of crushed stone. Depending on the requirements, the dimensions of one pebble can be from 5 to 200 mm, and the customer performing construction work may well order crushed stone of the required fraction. In most cases, the fraction is regulated by the GOST corresponding to the work and cannot be changed arbitrarily - this will negatively affect the quality of the work.
Adhesion
The second most important factor determining technical specifications crushed stone, is adhesion.
Adhesion is the ability of an individual grain of crushed stone to adhere to cement mortar or other building components. Usually the degree of adhesion is determined visually - the darker the crushed stone, the higher the degree of adhesion. It depends on the source rocks from which the crushed stone is made; dark, igneous rocks are stronger and, when ground, produce more uneven edges, which ensures proper adhesion.
Flakiness
The third parameter influencing the choice of crushed stone as building material, is its flakiness.
Flakiness is the presence of flat grains and individual plate-shaped pebbles in the crushed stone mass. Unlike the previous parameter, the flakiness value of good crushed stone should be as low as possible. Lamellar - flakier - are considered grains whose thickness and width are three or more times less than their length. Depending on the percentage of flakier grains in the crushed stone mass finished product divided by three main trade groups:
- cuboid– weight of flakier grains less than 15%;
- improved– mass of flakier grains from 15% to 25%;
- regular– mass of flakier grains from 25% to 50%.
The cuboid group is most highly valued, since in addition to higher strength, it also has good filling and compaction properties. Lamellar grains leave a lot of voids during cooking concrete mixture, and this leads to increased consumption of the solution and, as a consequence, to an increase in the cost of the construction process. Therefore, cube-shaped crushed stone is considered to be of the highest quality and more expedient to use from an economic point of view.
Strength
In addition to the three main characteristics mentioned above, there is also the strength of crushed stone - that is, wear resistance, determined during the crushing process. Strength is not only the ability of a stone to be destroyed in a crushing apparatus, but also its resistance to compression and crushing. Strength is one of the the most important characteristics during road construction work.
Frost resistance
It is also worth mentioning frost resistance - an important factor for Russian latitudes. This indicator demonstrates how much deep freezing and subsequent thawing crushed stone can withstand without compromising strength and, as a consequence, adhesion.
Radioactivity
Well, the last characteristic is radioactivity. Every natural material has its own degree of radioactivity, often this is a minimal natural background, but there are also certain incidents. This indicator determined only by the sanitary-epidemiological station, which has a license to issue such conclusions. Depending on the degree of radioactivity, the range of works in which the use of crushed stone as a building material will be permitted is outlined.
Main types of crushed stone
Crushed stone is divided into several groups according to the types of rocks from which it is produced.
Granite crushed stone
The most widespread type of crushed stone. Granite is frozen ancient magma, once upon a time, during the period of geological formation earth's crust thrown up from the depths by volcanoes globe. Contains inclusions of mica, spar, quartz and other things. Thanks to these inclusions, it can deservedly be considered the most durable of all. existing species crushed stone
Granite crushed stone comes in only two types: durable and high-strength. This type of material has increased frost resistance, minimal flakiness and practically zero content of various impurities.
Granite is deservedly very popular among builders. Its cuboid shape makes this crushed stone an excellent filler for various mixtures. In addition, depending on the number of inclusions of spar or quartz, this crushed stone can be of a variety of colors - from almost white to pink-red, and this is an excellent indicator for using it for finishing and decorative purposes.
Limestone crushed stone
As the name suggests, this type of crushed stone consists almost entirely of limestone rocks. Limestone is a product of organic decomposition, sedimentary rock, formed on the site of ancient seas. Unlike granite, it lies in layers that are clearly visible in the cross-section of the mountain range. Depending on natural chemical additives - iron, sulfur and others - limestone can be either white or pink, brown and yellow.
In terms of strength and conditions of use, limestone crushed stone is noticeably inferior to granite, therefore it is used mostly either in road work or in finishing. However, limestone is a very frost-resistant material, in addition, its environmental characteristics are also beyond praise. Such gravel does not contain various impurities, including harmful and radioactive nuclides.
crushed gravel
In addition to being used in its pure, finished form, gravel also serves as a material for making crushed stone from it. This happens when the gravel is too large in size of individual grains, that is, in its fraction, and requires additional grinding - screening.
This type of crushed stone is distinguished by fairly high technical characteristics, close to those of granite crushed stone. However, during the production of crushed gravel, a certain amount of sedimentary impurities is formed in the form of sand, clay, and organic matter, which is why this type of crushed stone requires additional sifting.
Due to its high performance and low cost, crushed gravel often acts as a substitute for granite crushed stone, serving as a filler for concrete. However, this type of crushed stone is most widely used in road construction, both in the production of asphalt directly and as drainage.
The use of crushed stone and gravel in construction work today is simply irreplaceable. These components of the fine fraction are very similar to each other. Each of them is formed from rocks and is widely used in construction. But still, despite the same origin, as well as external similarity, gravel and crushed stone have a significant difference. Each of them has its own application features. In addition, they interact with materials differently, and such indicators are very important during construction.
What is gravel made from?
Gravel is a mountain loose sedimentary rock of a rounded shape, with unclear edges. It contains small particles of minerals that are formed as a result of the natural and rather long-term destruction of hard rocks.
Gravel is classified into three types depending on the size of its particles:
- fine (particle size - 1-2.5 mm);
- medium stone (from 2.5 to 5 mm);
- coarse gravel (fractions 5-10 mm).
Industrial stone is used in foundation laying and road construction.
Depending on where gravel is mined, it can be mountain, river, lake, glacial, or sea. Unlike mountain, sea and river minerals have a smoother surface, which is why it was the first type that was found wide application in construction.
Mountain gravel is widely used in road construction, foundation construction, backfilling, as a filler for heavy concrete, etc.
The stones are different color scheme: They can be black, pink, yellow, brown, blue.
Gravel serves as a good design raw material and is used for arranging gardens and paths, and finishing flower beds.
In the composition of gravel you can often find the presence of various impurities, such as sand, soil, which impairs adhesion to concrete.
Features of crushed stone
Crushed stone is the result of crushing rocks of boulders, granite and limestone, but it is obtained by using special equipment, rather than waiting for natural destruction. The difference between gravel and crushed stone lies, first of all, in appearance: crushed stone is rougher, often has sharp corners, and in addition, its size is larger. All these qualities provide good grip various materials and surfaces.
This stone has different shapes. Due to this property, it is successfully used not only in construction work, but also in landscape design.
Types of crushed stone
Let's consider the types of crushed stone and its application.
Depending on the size of the mineral, they are distinguished:
- Granite screenings up to 5 mm in size. Used for covering sports fields and protecting city roads from ice.
- Crushed stone from 5 to 10 mm. Used for the manufacture of concrete and floor slabs.
- Sizes from 5 to 20 mm are suitable for making foundations, concrete, roads and bridges, pouring bridge structures.
- The average fraction is 20-40 mm in size. Ideal for building roads, preparing reinforced concrete and concrete, and building foundations for large houses.
- The large fraction is considered to be from 40 to 70 mm. Widely used for building houses and roads.
- For decorative purposes, crushed stone is used, the size of which is 70-120 mm.
Among the advantages are strength and frost resistance.
Gravel and crushed stone: the difference
There is a difference between crushed stone and gravel, but visually it is not very clearly visible. Their similarities are that they have the same origin and both are formed from rocks. In addition, these materials are widely used in construction; crushed stone (or gravel) is used for foundations, etc. There are also external similarities, for example, they can be the same in color.
Crushed stone is larger in size, has a more uneven surface, and has better adhesion. Thanks to all these characteristics, this material is in great demand on the Russian market. But it is quite easy to confuse ordinary crushed stone with mountain gravel, since the difference between them is very small. Both of these stones are inorganic, meaning their composition is very similar.
Gravel, as already noted, can be river, sea, etc. Its use and beneficial properties depend on this. As a rule, it has rounded shapes and a smooth surface, due to which it is often used to decorate facades, gardens, roads, etc.
Differences in cost
Depending on what rock the crushed stone is made from, there are several varieties. Each of them has its own cost. The price for large-sized fractions is slightly lower than for finely dispersed ones.
The final cost depends on the volume of material purchased. To compare the difference between gravel and crushed stone in price, we will indicate the average prices. Cost of 1 m 3 of crushed stone:
- limestone - 1500 rubles;
- gravel - on average 1,780 rubles;
- granite - 2100 rub.;
- secondary - 1150 rub.
The average price of 1 m 3 of gravel is 1,700 rubles.
The cost of these materials, as we see, is approximately the same, despite the fact that the costs of their production are different.
Summarize
So, which is better - crushed stone or gravel, and what are their differences?
Let us highlight the main characteristics of these materials:
- Crushed stone is formed as a result of mechanical crushing, or rather an explosion, and gravel is obtained as a result of the natural destruction of rocks.
- Crushed stone has a wider size chart and is used for various construction works. Gravel is used more for decorative purposes, although sometimes it can be used in the construction of a foundation. This is due, first of all, to the shape of the material: gravel is smoother, while crushed stone is angular, resulting in better adhesion to concrete and other building materials.
- The main advantages of crushed stone are its excellent adhesion and good physical properties, and gravel has a decorative appearance.