Sand density. What properties of building sand are affected by its density? Specific gravity of building sand kg m3

Sand is used in almost all areas of production, but especially a lot of it is required for construction work. Without sand, it is impossible to prepare concrete, build a foundation or pour a blind area. The preparation of concrete and other building mixtures is based on the use of various materials in a certain proportion. Therefore, it is very important to be able to correctly determine the specific gravity of construction sand.

The specific gravity of sand and methods for its determination

Specific gravity or specific gravity is the weight of sand contained in a certain volume. Usually, this value is indicated by the weight of sand, measured in kilograms, contained in a volume equal to one cubic meter. However, in the technical literature there is another designation for the specific gravity of sand - tons / cubic meter and grams / cubic centimeter. The specific gravity of building sand in kg / m3 is calculated by the formula:

m=V*p, where the weight of the sand is m; its volume is V and its density is p.

Knowing the weight of the sand and the degree of its density, which is reported by the supplier, it is possible to determine the specific gravity. It is not necessary to do calculations, as you can use the reference data or perform the calculation on the online calculator.

Factors Influencing the Specific Gravity of Sand

The weight in 1 m3 depends on its density. And the density value is influenced by many factors, of which the following are considered the main ones:

the amount of impurities contained in the sand;
composition of minerals;
the size of individual grains of sand (fractions);
compaction percentage;
humidity level;
storage method.

In the regulatory literature (for example, in GOST 8736 of 1993), the average value of the specific gravity of construction sand is 1500 kg / m3. For the same type of sand with other moisture and density indicators, the following standard data are used:

dry sand - 1440 kg/m3;
sand dry and compacted (compacted) - 1680 kg/m3;
wet sand - 1920 kg/m3;
wet and compacted sand (compacted) - 2545 kg/m3.

Volumetric weight of construction sand in kg/m3

In some cases, when it is not possible to weigh the sand, its volumetric weight is determined - how many kilograms of sand are in a predetermined volume. The value of the volumetric weight is variable, since the following parameters influence its value:

humidity;
specific gravity;
density.

Therefore, the volumetric weight of sand in 1 m3 is most often determined from tables in reference books or using an online calculator. An incorrectly determined weight of m3 of sand can lead to a deterioration in the quality of concrete and cement-sand mortar, to a decrease in their strength, and even to premature destruction of manufactured structures.

Buy sand in our company

According to its technical characteristics, all of them meet the requirements of GOST 8736 of 2014 and, when sold, are accompanied by a certificate of conformity, which must indicate the specific gravity of the sand. Call and or self-delivery of high-quality construction sand.

The name of the sand, type or variety.	Other name.	Bulk density or specific gravity in grams per cm3.	Bulk density or specific gravity in kilograms per m3.	-	-	-
Dry.	Dry sand.	1.2 - 1.7	1200 - 1700	-	-	-
River.		1.5 - 1.52	1500 - 1520	-	-	-
River compacted.	Sand from the river, washed without clay fraction.	1.59	1590	-	-	-
River grain size 1.6 - 1.8.	Sand from the river, sand mined in the river, sand from the bottom of the river.	1.5	1500	-	-	-
River alluvial.	Sand from the river, sand washed up in the river, sand from the bottom of the river obtained by the alluvial method.	1.65	1650	-	-	-
River washed coarse-grained.	Coarse-grained sand from the washed river.	1.65	1400 - 1600	-	-	-
Building.	sand for construction, sand for construction and finishing works, sand used and used in construction.	1.68	1680	-	-	-
Construction dry loose.	Sand for construction, sand for construction and finishing works, sand used and used in construction.	1.44	1440	-	-	-
Construction dry compacted.	Compacted sand for construction, compacted sand for construction and finishing works, compacted sand used and used in construction.	1.68	1680	-	-	-
Career.	Quarry sand, quarry sand.	1.5	1500	-	-	-
Quarry fine-grained.	Fine-grained sand from a quarry, fine sand mined in a quarry.	1.7 - 1.8	1700 - 1800	-	-	-
Quartz regular.	Sand from quartz.	1.4 - 1.9	1400 - 1900	-	-	-
Quartz dry.	Sand from quartz.	1.5 - 1.55	1500 - 1550	-	-	-
Quartz sealed.	Sand from quartz.	1.6 - 1.7	1600 - 1700	-	-	-
Nautical.	Sand from the sea, sand from the seabed.	1.62	1620	-	-	-
Gravely.	Sand mixed with gravel.	1.7 - 1.9	1700 - 1900	-	-	-
Dusty.	Sand mixed with dust.	1.6 - 1.75	1600 - 1750	-	-	-
Dusty compacted.	Compacted sand with an admixture of dust.	1.92 - 1.93	1920 - 1930	-	-	-
Dusty water-saturated.	Sand mixed with dust.	2.03	2030	-	-	-
Natural.		1.3 - 1.5	1300 - 1500	-	-	-
Natural coarse.	Sand in natural origin, usually quartz.	1.52 - 1.61	1520 - 1610	-	-	-
Natural medium grain.	Sand in natural origin, usually quartz.	1.54 - 1.64	1540 - 1640	-	-	-
For construction work - normal humidity according to GOST.	Construction sand.	1.55 - 1.7	1550 - 1700	-	-	-
Expanded clay grade 500 - 1000.	Sand from expanded clay.	0.5 - 1.0	500 - 1000	-	-	-
Expanded clay size of firm grains (particles) - fraction 0.3.	Sand from expanded clay.	0.42 - 0.6	420 - 600	-	-	-
Expanded clay size of firm grains (particles) - fraction 0.5.	Sand from expanded clay.	0.4 - 0.55	400 - 550	-	-	-
Mountain.	Quarry sand.	1.5 - 1.58	1500 - 1580	-	-	-
Fireclay.	Chamotte sand.	1.4	1400	-	-	-
Forming normal humidity in accordance with GOST.	Sand for molding parts, foundry sand, sand for molds and casting.	1.71	1710	-	-	-
Perlite.	Expanded perlite sand.	0.075 - 0.4	75 - 400	-	-	-
Perlite dry.	Expanded dry perlite sand.	0.075 - 0.12	75 - 120	-	-	-
Ravine.	Sand lying in ravines, sand from a ravine.	1.4	1400	-	-	-
Alluvial.	Alluvial sand, alluvial sand.	1.65	1650	-	-	-
Medium size.	Medium sand.	1.63 - 1.69	1630 - 1690	-	-	-
Large.	Coarse sand.	1.52 - 1.61	1520 - 1610	-	-	-
Medium grained.	Medium grain sand.	1.63 - 1.69	1630 - 1690	-	-	-
Small.	Fine grained sand.	1.7 - 1.8	1700 - 1800	-	-	-
Washed.	Washed sand from which soil, clay and dust fractions are removed.	1.4 - 1.6	1400 - 1600	-	-	-
Compacted.	Sand artificially compacted and rammed.	1.68	1680	-	-	-
Medium density.	Sand of normal density, normal, medium density for construction work.	1.6	1600	-	-	-
Wet.	Sand with high water content.	1.92	1920	-	-	-
Wet compacted.	Sand with a high water content is compacted.	2.09 - 3.0	2090 - 3000	-	-	-
Wet.	Sand with high humidity, different from normal according to GOST.	2.08	2080	-	-	-
Water-saturated.	Sand deposited in an aquifer.	3 - 3.2	3000 - 3200	-	-	-
Enriched.	Sand after enrichment.	1.5 - 1.52	1500 - 1520	-	-	-
Slag.	Sand from slag.	0.7 - 1.2	700 - 1200	-	-	-
Porous sand from slag melts.	Slag sand.	0.7 - 1.2	700 - 1200	-	-	-
Swollen.	Perlite and vermiculite sands.	0.075 - 0.4	75 - 400	-	-	-
Vermiculite.	Swollen sands.	0.075 - 0.4	75 - 400	-	-	-
Inorganic porous.	Porous light sand of inorganic origin.	1.4	1400	-	-	-
Pumice.	Pumice sand.	0.5 - 0.6	500 - 600	-	-	-
Aggloporite.	Sand obtained after the burnout of minerals - burnout of the original rock.	0.6 - 1.1	600 - 1100	-	-	-
diatomite.	Sand is diatomaceous.	0.4	400	-	-	-
Tuff.	The sand is tuff.	1.2 - 1.6	1200 - 1600	-	-	-
Eolian.	Natural sand formed naturally as a result of eolian weathering of hard rocks.	2.63 - 2.78	2630 - 2780	-	-	-
The ground is sand.	Sand in natural occurrence, soil with a very high content of sand.	2.66	2660	-	-	-
Sand and gravel.	Construction Materials.	sand 1.5 - 1.7 and crushed stone 1.6 - 1.8	sand 1500 - 1700 and crushed stone 1600 - 1800	-	-	-
Sand and cement.	Construction Materials.	sand 1.5 - 1.7 and cement 1.0 - 1.1	sand 1500 - 1700 and cement 1000 - 1100	-	-	-
Sand and gravel.	A mixture of sand and gravel.	1.53	1530	-	-	-
The sandy-gravel mixture is compacted.	A mixture of sand and gravel.	1.9 - 2.0	1900 - 2000	-	-	-
The battle of the usual red clay brick.	Sand obtained by crushing red ceramic clay bricks.	1.2	1200	-	-	-
Mullite.	Mullite sand.	1.8	1800	-	-	-
Mullite-corundum.	Mullite-corundum sand.	2.2	2200	-	-	-
Corundum.	Corundum sand.	2.7	2700	-	-	-
Cordierite.	Cordierite sand.	1.3	1300	-	-	-
magnesite.	Magnesite sand.	2	2000	-	-	-
Periclasospinel.	The sand is periclase spinel.	2.8	2800	-	-	-
from blast furnace slag.	Slag sand from blast-furnace slag.	0.6 - 2.2	600 - 2200	-	-	-
From waste slag.	Slag sand from waste slag.	0.6 - 2.2	600 - 2200	-	-	-
from granular slag.	Slag sand from granular slag.	0.6 - 2.2	600 - 2200	-	-	-
From slag pumice.	The sand is slag pumice.	1.2	1200	-	-	-
from ferrotitanium slag.	The sand is slag pumice.	1.7	1700	-	-	-
Titanium aluminous.	Titanium aluminous sand.	1.7	1700	-	-	-
Basaltic.	Sand from basalt.	1.8	1800	-	-	-
Diabase.	Sand from diabase.	1.8	1800	-	-	-
Andesite.	Andesite sand.	1.7	1700	-	-	-
Diorite.	Diorite sand.	1.7	1700	-	-	-
From scrap heat-resistant concrete with fireclay filler.	Sand from heat-resistant concrete scrap with fireclay aggregate.	1.4	1400	-	-	-

Some explanations for the question.

As you have already noticed, it is quite difficult to find a clear answer to a specific question on the Internet: what is the density of sand or its specific gravity. A search engine, such as Yandex or Google, provides a lot of information. But all of it is rather "indirect" in nature, rather than accurate and understandable. The search engine selects different mentions, snippets of phrases, lines from large and obscure tables of the specific gravity of building materials, in which values \u200b\u200bare very chaotically given in different systems of units. "In passing" on the sites "falls out" a large amount of "additional" information. Mainly: according to the types and varieties of sand, its use, application, origin, mineralogical composition, color, solid particle size, color, impurities, mining methods, cost, price of sand and so on. Which adds uncertainty, inconvenience to normal people who want to quickly find an accurate and understandable answer: how much is the density of sand in grams per cm3. We decided to “correct the situation” by bringing together data on different types of sand into one common table. Having excluded in advance the “superfluous”, in our opinion, “passing” information of a general nature. And indicating in the table only exact data, what is the density of sand.

What is the density of sand or its specific gravity (volumetric gravity, specific gravity - synonyms)? The density of sand is the weight that fits in a unit of volume, which is most often considered cm3. Quite objectively, the issue is complicated by such a situation that the sand itself has many types that differ in mineralogical composition, the size of the fraction of solid particles in the sand, and the amount of impurities contained. Impurities in the sand can be clay, dust, crushed stone, stone chips and larger stones. Naturally, the presence of impurities will immediately affect the sand density determined by laboratory methods. But most of all, the density of sand will be affected by its humidity. Wet sand is heavier, weighs more and immediately significantly increases the specific gravity per unit volume of this material. What is related to its value when buying and selling. For example, if you want to buy sand by weight, then its sale should be tied to the so-called normal moisture content, determined by GOST. Otherwise, by buying wet or damp sand, you run the risk of losing a lot on its total amount. In any case, for the consumer, it is much better to buy sand measured in units of volume, such as cubic meters (m3), than in units of weight (kg, tons). The moisture content of sand affects its density, but has very little effect on volume. Although there are some "subtleties" here. More dense wet and wet sand, occupies a slightly smaller volume than dry sand. Sometimes this needs to be taken into account. The specific gravity of the sand contained in the selected volume, that is, the density, will largely be affected by the “laying method” of it. Here, it is understood that sand of the same type can be: in a state of natural occurrence, be under the influence of the weighing effect of water, be artificially compacted or simply poured. In each case, we have completely different values, how much is the density of this type of sand. Naturally, it is difficult to reflect all this diversity in one table. Some data must be sought in the specialized literature.

Among all the numerous options for the density of dry sand, only one is usually of practical interest to site visitors - this is bulk density. It is for her that we give the values \u200b\u200bof the specific gravity of dry sand in the table. It is useful to know that there is another density - this is the true density of dry sand. How to define it? It is determined by laboratory methods or calculated by a formula. Although, it is more convenient to use the reference data in a special table. The true density of dry sand gives us a different specific gravity - a theoretical one, which is always much higher than those values of the specific gravity of dry sand that are used in practice and are considered technological characteristics of the material. With some reservations, the true specific gravity of dry sand can be considered the density of solid particles (grains) included in its composition. By the way, when determining the bulk density, and hence the technological specific gravity of dry sand, the size of the grains also plays a certain role. This characteristic of the material is called grain size. In this case, in this table we are considering medium-grained dry sand. Coarse-grained and fine-grained are used less often and their specific gravity values may differ slightly. Not only the grain size, but the mineralogical composition of this bulk building material can be different. This table shows the bulk density of a material consisting predominantly of quartz grains. Quantity and weight are measured in kilograms (kg) and tons (t). However, let's not forget about other types of material. On our site you can find more specific information that is rarely found on the Internet.

Note.

The table shows the density of sand of the following types: river ordinary, river natural, river compacted, river with a grain size of 1.6 - 1.8, river alluvial, river washed coarse-grained, construction ordinary, construction loose, construction compacted, quarry ordinary, quarry fine-grained, quartz natural, dry quartz, compacted quartz, marine, gravelly, dusty, compacted dusty, water-saturated dusty, natural, natural coarse-grained, natural medium-grained, for construction work of normal humidity according to GOST, expanded clay grade 500 - 1000, expanded clay with a hard grain size of 0.3, expanded clay with a size hard grains 0.5, mountain, fireclay, molding with normal humidity according to GOST, perlite, dry perlite, ravine, alluvial, medium size, coarse, medium-grained, fine, washed, compacted, medium density, wet, wet compacted, moist, water-saturated, enriched , slag, porous from slag melts, vermic ulite, expanded, inorganic porous, pumice, aggloporite, diatomite, tuff, aeolian, soil sand, sandy gravel mixture, sandy gravel mixture compacted, from the breakage of ordinary red clay ceramic bricks, mullite, mullite-corundum, corundum, cordierite, magnesite, periclase spinel, from blast-furnace slag, waste slag, granulated slag, slag pumice, ferrotitanium slag, titanium-alumina, basalt, diabase, andesite, diorite, from heat-resistant concrete scrap with fireclay filler and some other types.

Sand is a loose natural material obtained as a result of the natural destruction of rocks under the influence of external factors. It may contain a small amount of various impurities. It is used in almost all types of construction. To properly mix the solution, you need to know the density of the sand, since the proportions of the remaining components depend on it. It also affects the volume of purchases, for example, for arranging a pillow under the foundation.

What is density and what does it depend on?

Density shows how many grains of sand in kilograms are placed in 1 m3. It is measured in kg / m3, sometimes in t / m3 or g / cm3 (this indicator affects). But this value is not always constant, as it can change depending on the following conditions:

1. Grain size. It happens fine-, medium- and coarse-grained. The larger the grain of sand, the lower the density, and, conversely, the finer ones fit more densely. Coarse and medium-sized sands are used for the manufacture of building materials and masonry mortars, while fine-grained sands are used for the production of dry building mixtures.

2. Porosity. Shows the number of voids. The high porosity option has a lower density. If it is loose, then the value is 47%, if compacted - 37%. The degree of porosity decreases when the sand grains are saturated with moisture, as they are enveloped in water and the voids between them disappear. It also decreases after transportation, as during movement everything is compacted due to vibration. Different fractions have different degrees of porosity. For building sand from large and medium grains, it is 0.55, for fine sand - 0.75. The denser it is laid, the greater the load from the foundation is able to withstand and distribute it more evenly.

3. Moisture coefficient. Before buying, be sure to check the degree. The more water it contains, the lower the density. The weight of 1 m3 of raw sand differs significantly from the same amount of dry sand.

4. Impurities. Depending on their volume, the density of sand kg/m3 also changes. It may contain clay, dust, salt, gypsum and more. The density of pure material is about 1300 kg/m3, with clay impurities - 1800 kg/m3. To remove contaminants, it is washed, but because of this, the cost increases markedly.

Types and prices

There are several types of densities:

true;
bulk (medium).

The first type is otherwise called specific gravity, it is also measured in kg / m3. The true density shows how much is in one cubic meter of bulk building material, without taking into account the voids between the grains. Calculate it in laboratories empirically. Its value for non-metallic sandy rock is 2500 kg/m3.

Bulk density shows the amount in one cubic meter, taking into account voids and gaps. Its value is always less than the true value. To measure it, you need a bucket of 10 liters. Sand in the usual uncompacted state is poured from a height of 10 cm from the edge of the container, until a slide appears above it. As soon as the bucket is full, the excess is leveled with a metal ruler, without compacting the sand, after which the container is placed on the scales. The result obtained must be divided by the number 0.01, which means the volume of the bucket, converted to cubic meters. For example, sand weighs 16.5 kg, it is equal to: 16.5 / 0.01 = 1650 kg / m3. In this case, it is convenient to use the formula P=M/V, where P is the density, M is the mass, V is the volume. And, conversely, knowing the compaction index, it is calculated how much the bulk building material weighs, for this it is multiplied by the volume of the container - M \u003d P * V.

The true density of building sand is a constant value. For calculations, the average value is used. Prices vary depending on its type, purity and size of fractions. Uncleaned is much cheaper than washed. Therefore, if a small batch is required, then unwashed sand can be purchased and cleaned of impurities on its own, especially if it is necessary for the construction of an unloaded structure. If you need to make a foundation, then you should purchase only clean and high-quality material. Clay and other impurities reduce the degree of adhesion of grains of sand to cement, which reduces the strength grade of concrete.

Table with prices at which you can buy building sand:

When choosing sand, one should take into account: the lower its density, the more binder powder is required to fill the voids between the grains of sand and connect all the components, as a result, the cost of the mortar increases.

The degree of radioactivity of most bulk building materials is the first, but it is better to check the quality certificates, especially if it will be used to build a house, in this case only the first class should be.

The first plan is the issue of acquiring materials. To calculate how much sand to buy for mixing the required volume of masonry, you need to know the density of the bulk component. This indicator significantly affects the strength parameters of structures and buildings. The conversion of mass into volume (and vice versa) is also carried out because the price of the material is indicated in different ways: per weight or volume unit.

What is density and what does it depend on

This is a physical characteristic of a substance, showing the mass of its unit volume and expressed in g / cm3, kg / m3, t / m3. Sand, like all bulk materials, has the following feature: depending on the conditions, the same amount of sand can occupy a different volume. The density index of building sand is influenced by the following factors.

1. Grain size (fineness modulus). Sand is a mixture of particles ranging in size from 0.14 to 5 mm, formed naturally during the destruction of rocks. The smaller the grain size and the more uniform the composition, the denser the sand. Coarse and medium-grained material is used for the manufacture of concrete, fine-grained - for cement mortars, fine-grained (pulverized) - for building fine mixtures.

2. Porosity and level of compaction. They characterize the number of voids in the bulk material. In a loose state, building sand has a porosity of about 47%, in a dense state - no more than 37%. Looseness is reduced due to saturation with moisture, vibration, dynamic effects. Porosity is estimated using a special coefficient e: for fine-grained sands of dense composition, it is about 0.75, coarse and medium-grained - 0.55. The compacted sand mass takes on fairly high loads and distributes the stress that occurs in the foundations well.

3. Humidity. Usually, reference books give density at a normal humidity level, regulated by GOST. When buying, it should be borne in mind that the weight of a cubic unit of raw material differs significantly from the theoretical indicator. With an increase in humidity from 3 to 10%, the grains of sand are enveloped in water - due to this, the volume increases, and the density, respectively, decreases. With further moisture saturation (up to 20%), water displaces air and fills the voids between the grains - while the weight of a cubic meter increases.

4. The presence of impurities. Sometimes particles of clay, dust, salt, mica, gypsum, humus, crushed stone, stone chips are contained. They affect the quality characteristics of the building material: if for pure sand it averages 1,300 kg / m3, then for clay - 1,800 kg / m3. Sand can be cleaned by washing with water, but this increases its cost.

Types of density

Building sand can be characterized using different indicators of its volumetric weight: theoretical and actual.

1. True (former name - specific gravity). This is the mass of a cubic meter in an absolutely compacted state, without taking into account between particles. The true indicator is determined in a complex laboratory way, its value corresponds to the weight of a cubic meter of solid non-metallic sandy rock - approximately 2500 kg / m3.

2. Medium (bulk). When determining it, it is taken into account that the calculated volume includes not only grains, but pores and voids that fill the gaps between them. The average is usually below the true value.

To independently determine the average density, use a bucket with a capacity of 10 liters. Sand is poured into it from a height of 10 meters until a hill forms - it is carefully cut horizontally at the level of the upper edge of the bucket. The material that fits in the container is weighed, and then its density is calculated in kg / m3: divide the mass in kg by 0.01 (the volume of the bucket in cubic meters).

The true value is a constant value and has an auxiliary value. In order to competently conduct construction, make practical calculations and evaluate the quality of the purchased material, it is more important to know the average. For example, if a cubic meter weighs less than 1300 kg, this indicates a large number of voids and requires them to be filled with a binder. At the same time, the cost of materials increases, making construction more expensive.

The approximate indicators of bulk (average) density indicated in the table will help you purchase sand with the necessary parameters, quickly switch from weight to volume, and calculate the weight fractions of the mortar.

Density is represented by a physical quantity characterized by a certain amount of a substance, expressed in grams or kilograms, per unit volume. This indicator, characteristic of bulk substances, including sand, cannot be unambiguously determined. This is due to the fact that the volume in which the same amount can fit can be different. The indicator is influenced by several factors, among them:

degree of tamping;
humidity percentage;
fraction structure;
porosity;
all kinds of inclusions.

Density Level Determination

The density of sand acts as the main parameter, the level of which determines the scope of its application and the final strength of buildings and structures. The described characteristic is required to calculate the consumption of sand when it is necessary to obtain a certain volume of building mixture.

In addition, in some cases it becomes necessary to convert the mass of sand into volume or vice versa. If it is necessary to determine the mass of 1 m 3 of sand or calculate the volume of a ton of the mentioned material, then the following steps must be taken.

The density of sand or any other material can be determined by dividing the mass (M) by the volume (V) that was occupied by it. So, ρ=M/V. The mass of material that occupies a certain volume can be determined using the following formula: M=ρ*V. But the volume can be calculated if the exponent ρ and mass are known. So, the volume is determined by the formula: V \u003d M / ρ.

In the preparation of mortars, mixtures and in the construction of structures based on concrete, sand should be used in a given proportion in relation to the rest of the components. In order to correctly determine the proportion of sand in these mixtures or structures, it will be necessary to know exactly what its density index is.

If you make calculations with an error, then the amount of sand in the total volume will be insufficient or excessive. If you make up for the lack of sand, then most likely you will have to do this at the expense of more expensive components, which will lead to an unjustified increase in the cost of the entire mixture. Whereas if the amount of sand turned out to be greater in the volume of the mixture, this will cause a decrease in the quality of the products or solution. Due to this, frost resistance, abrasion resistance and water resistance will suffer, as a result, the master will receive products or designs whose characteristics will differ from those provided by the standard.

Back to index

Types of indicator ρ

Sand is characterized by some types of density, among them: true, bulk and average.

On fig. 1 is a table in which you can see the bulk density of sand in different states. If we consider this material, then it is represented by a solid rock of non-metallic origin. This explains the fact that it has an indicator approximately equal to 2500 kg / m 3. This indicator is the true density. If it is necessary to make calculations for use in practice, another indicator should be used - bulk. It characterizes building materials in an unpacked form and is calculated taking into account the volume of grains and the hollow space that remains between them. This leads to the fact that the level of bulk density in all cases is less than the true one. But when tamping a material that is in a loose state, it is possible to increase its level ρ. So, if the material is in the body of the car, then it has a natural, unpacked state and a bulk level is characteristic of it. If this value is known, then it is possible to determine the volume and mass of the material. This is important, because the cost of transporting building materials can be calculated not only by weight, but also per 1 m 3 of volume.

The density of sand, which is in a bulk state, is 1300-1500 kg/m 3 . The level of humidity of the external air can affect the volume of the material, this entails variations in the level of bulk density. If the humidity becomes greater, then this entails a decrease in the level ρ of the material. This is due to the adhesion of grains. The decrease in this level can last until the humidity reaches 10%. After that, moisture particles entail an increase in the volume of liquid in the building material, while the level ρ begins to rise. This feature of the change in the indicator under consideration should be taken into account if the dosage is by volume.

Back to index

Bulk level calculation ρ

In order to calculate the grain density in the bulk state, the material must be sifted in advance using a sieve with a mesh size of 5 mm. After that, it must be placed in a measuring vessel of 1 liter. At the same time, it must be freely filled from a height of 10 cm, forming a cone above the vessel, which must be cut off using a ruler. You need to know how much the vessel weighs in an empty and filled state. It is permissible to calculate the bulk level using the formula: ρн=(m2-m1)/V. In it, m1 and m2 are the masses of the vessel in an empty and filled state, while V is its volume. The table may not be needed, since all calculations can be done independently.

The level of the average index ρ is influenced by voids and humidity. There is a dependence: with fewer pores, this figure is higher. It can be assumed that ρ characterizes the fractional composition.

Its average level varies for certain types of sand. Dry material based on quartz in its natural state has a density index in the range of 1500-1550 kg/m 3, while in the compacted state this level is 1600-1700 kg/m 3 . This indicates that the average density index is determined by the structure of the fractional composition.

If you need to make concrete that will have the qualities of high strength and resistance to frost, then you should use a material that has an increased average density.

During construction, you can use the data of the tables, but you should be aware that in a loose state, the quartz material has ρ in the range of 1500 kg / m 3, but the level can reach 1700 kg / m 3.

In order to determine the bulk density, you can use not only the measurement method that was described above. By the way, an ordinary construction bucket can also be used as a vessel. These calculations will allow you to get the closest to the true result. If you use a bucket, then you can use a scoop to pour the material.