Weight of 1 m3 of wood. How much chopped firewood weighs, the weight and mass of dry firewood and firewood with natural moisture, depending on the type of wood. Weight of a cubic meter of wood of different humidity

During construction work involving the use of lumber from coniferous trees, correct calculations of the specific gravity of pine wood are very important. Unlike other various building materials, this variety does not have a single specific gravity, which somewhat complicates the selection process. The fact is that pine wood, like any wood, is a natural porous material. Accordingly, depending on the type of pine and the percentage of humidity, the specific gravity of the pine changes.

As mentioned above, the main parameter affecting the volumetric weight of pine is humidity. For example, the highest specific gravity is found in still untouched, growing pine. This is due to the fact that the tree requires high humidity to grow. At the same time, humidity is both a useful substance and a carrier of other, no less useful, vitamins and minerals. The amount of moisture depends entirely on the type of pine, the harvesting season and the area. Humidity levels of “live” pine can vary from 29% to 81%. The lowest indicator, respectively, is for dried pine, since the humidity in this state tends to zero.

Table of weight of 1 m3 of pine depending on its humidity.

It is very difficult to determine the percentage of moisture using improvised means. And this is a very important indicator for determining such a parameter as the specific gravity of a cubic meter of pine. Typically, these procedures are carried out in special technological laboratories.

The easiest way when purchasing a material is to check the moisture content from the manufacturer. Then, using the table presented, find out the weight of a pine cube with a flag from 5% to 90% and the density of the material:

Practical meaning and importance.

Among coniferous building materials, wet, dried, dry and damp pine trees are valued. However, these terms do not give a specific exact value for humidity, so knowing clear numbers is essential. For example, requirements for the use of fallen pine are not provided for by legislative acts. But, when performing certain work, GOST sets humidity standards, for example:

In this article about how much does a cube of pine weigh?(one cubic meter of pine wood), how to measure it correctly and on what parameters its weight depends.

Whether it is renovation, construction, or the usual procurement of heating material, correctly calculating the weight of a cube of pine is important, elementary in order not to be deceived by sellers and not to overpay.

How much does a cube of pine weigh - how does humidity affect it?

The same pine tree can have different weights. This is directly related to the amount of moisture in it. Depending on the percentage of water in wood there are dry, air-dry, wet and wet rocks.

• Pine, the humidity of which is equal to 10 to 18% is called dry and the weight of one cubic meter is 505-510 kilogram.
• If the humidity 19-23 % , then the mass of one cube is 520 kg.
• At 24-45% pine is considered raw and its weight will be about 550 kilogram.
• All wood whose moisture content exceeds 45 % called raw, a cubic meter of it weighs from 550 and up to 730 kilogram.
• A cube of a freshly cut pine tree can sometimes reach up to 820 kg, since its humidity exceeds 90% .

More specific information can be found using special tables that show the correspondence between the percentage of humidity and the mass of a pine cube.

The weight of wood also directly depends on its density. Density, in turn, is directly proportional to the moisture content of the wood. Dry pine has a density of 0.50-0.52 g/cm 3, and its cubic meter weighs approximately 515 kilograms.

Fully dried pine wood with a density of 0.48 g/cm 3 has a weight 480 kg, if the wood is damp, then the density is 0.64-0.85 g/cm3, 600 – 700 kg per cubic meter

In general, the higher the moisture content of the rock, the higher its density, and, accordingly, the greater the mass of one cubic meter of wood.

Information about the exact weight of pine (pine lumber) can be useful when transporting it and choosing the carrying capacity of vehicles.

In general, there are two types of wood weight:

1. Specific.
2. Volume.

Specific gravity is approximately 1540 kg/m3 and is defined as the mass of one cubic meter without taking into account various indicators, such as the type of wood, its humidity and density.

The volumetric weight depends on the moisture content of the tree and its species. Unit of measurement such weight - g/cm3. It is worth noting that it is customary to calculate it only at normal humidity, namely 15 % .

Define volumetric weight according to the following formula:

уw=y 0 (100+w) / (100+(Y 0 -Yw))

W – wood humidity;

Уw – volumetric shrinkage;

Y 0 – volumetric weight in a completely dried state;

уw – volumetric weight of wood.

There is another concept - conditional volumetric weight. It is defined as the ratio of the weight of a completely dry piece of wood to the weight of the same freshly cut sample. The overall humidity does not matter, so it is more convenient to use. It is calculated using the formula:

Y 0 =y conv /(1-y)

Where Y0 is the weight of dry wood, and y is the shrinkage of the rock, shown as a percentage.

You can do all the calculations yourself, or you can turn to special online calculators that will give you the exact answer in a few seconds.

I hope you liked the detailed answer

The average values ​​of the specific gravity (SG) of larch are calculated at a relative humidity of 12% without reference to the grade of wood. The value is undiluted without any applied value, taking into account humidity and grade. The specific gravity of larch does not affect quality indicators. In addition, it is impossible to calculate the indicator using only a cube of dry larch.

The effect of humidity on the weight of wood

The moisture content of the wood affects the weight of the wood. There are four degrees of humidity: dry (10-18%), air-dry (19-23%), damp (24-45%) and wet (above 45%). Thus, it turns out that wood species with the same moisture content differ in weight. Weight fluctuates relative to humidity. The standard humidity is 12%.

Density affects weight

Density also affects the weight of wood. The density of iron and ebony wood is 1100 - 1330 kilograms per cubic meter. Bog oak 950-1100 kg/m3. Beech, oak, acacia, pear and hornbeam with a density of 700 kg/cu. Pine, bamboo and alder have a density of 500 kg/m3. Cork has 140 kg/m3.

When buying lumber, it is difficult to determine the volume and quantity of products by eye. However, the dimensions of the product, humidity and wood used in production make it possible to calculate the exact weight of the product. Knowing how much a cube of wood weighs, you can choose the right transport for delivery.

The weight of edged larch boards 150*25*6000 mm is 15.5 kg.

Standard weight of a larch board 6 meters long:

The dimensions of the board are indicated in the “width/thickness” format:
60x19 (mm) – 4.72 (kg), 80x22 (mm) – 7.29 (kg), 100x22 (mm) – 9.1 (kg), 150x25 (mm) – 15.5 (kg), 200x32 (mm) – 26.5 (kg).

The weight of larch boards is calculated using the formula:

m = pxV, where “m” is mass (kg), “p” is density (kg/m3), “V” is volume (m3).

Important: the density of larch is a reference value and is 690 (kg/m3).

Weight of 1 cubic meter (1 m3) of larch wood:

• dry (W=10-18%) – 600-650 kg;
• in moisture-protected structures – 650 kg;
• impregnated – 800-900 kg;
• in a freshly cut state - 840 kg.

Weight of 1 cubic meter in kilograms

The board is a certain lumber that is up to 100 mm thick and, usually, twice as wide. It is made from beams or logs of various tree species as a result of longitudinal division of round timber and division of the resulting parts. All this production is carried out on special equipment and machines. This type of material is used in all areas of production or construction work where the use of wood is necessary.

When working with materials such as boards, it is necessary to take into account its quality. A characteristic such as specific gravity will help determine this parameter.

Board Specific Gravity Table

If the density of the material is known, the specific gravity of the board can be easily calculated without the use of specialized equipment. The average values ​​of such parameters as the weight of the board and the weight of 1 m3 of the board can be easily calculated using the table below.

Specific Gravity Calculations

In order to carry out the necessary calculations, it is necessary, first, to determine the value itself. Specific gravity is the ratio of the weight of the substance being sought to its occupied volume. All these calculations occur thanks to the formula: y=p*g, where y is the specific gravity, p is the density, g is the acceleration of gravity, which in normal cases is a constant and equals 9.81 m/s*s.

The result is measured in Newtons divided by cubic meter and denoted N/m3. In order to convert to the SI system, that is, to kg/m3, the resulting value must be multiplied by 0.102.

A parameter called density is the amount of its mass in kilograms that can fit in a cubic meter. A very ambiguous value that depends on many factors. The main factors for boards are humidity and wood type. So, this parameter can vary from 380 to 1330 kg/m3.

When designing various types of wooden structures, they often use such an indicator as the weight of the lumber from which they are supposed to be made. It would seem that such information can be obtained from specialized reference books. However, in such literature, unfortunately, only the weight of 1 m 3 of timber or, for example, boards is often indicated. Lumber is often purchased not by the cubic meter, but simply by the piece.

The length of timber sold by woodworking workshops may vary. But most often such enterprises sell 6 m of lumber to the public. So what, for example, can be the weight of timber with natural moisture content of 150x150x6000 mm? To find out, you will have to do a few simple independent calculations.

What determines the weight of lumber?

It is clear that the more moisture contained in the timber, the heavier it will be. However, the weight of such lumber depends not only on this factor. When performing calculations, in this case it is imperative to take into account the characteristics of the wood species itself. After all, for example, oak timber will in any case be heavier than birch lumber.

What is natural humidity

So, how to calculate the weight of a wooden beam of natural humidity 150x150x6000 mm of one species or another? Making such calculations is actually not too difficult. However, before starting calculations, it is still worth defining the concept of “natural humidity”.

In construction and in the manufacture of various types of products, only wood with a moisture content of no more than 12-15% is used. And even such boards and timber are in most cases additionally dried for some time before use.

The humidity of only cut wood will, of course, be very high. In any case, its figure will exceed 12-15% significantly. It is this kind of humidity that is usually called natural. That is, we ultimately need to know the weight of a standard-length wooden bursa with a cross-section of 15x15 cm, made from freshly sawn wood.

We take into account the breed

When performing such an operation, information from the table of lumber weights in cubic meters should be taken as a basis.

Calculations in this case are performed as follows:

find out the number of beams of a given length and cross-section in 1 m 3;

By simple division, the mass of one such unit of lumber is calculated.

One cubic meter of timber having dimensions of 150x150x6000 mm will thus contain 1: 0.15: 0.15: 0.15: 6 = 7.4 pieces. To find out the weight of the beam, in this case you need:

look at the weight per cubic meter for this particular type of wood;

divide this parameter by the number of beams per cubic meter.

For example, with a humidity of 15%, 1 m 3 of pine lumber weighs, according to the table above, 440 kg. That is, the calculation in this case will look like this:

440 / 7.4 = 59.5 kg.

It is also easy to determine that the weight of a 150x150x6000 mm larch beam of the same moisture content will be equal to 90.5 kg. For aspen, this figure will be 67.6 kg.

Instructions for calculating the weight of timber with natural humidity 150x150x6000 mm

Thus, it is not too difficult to find out the weight of lumber of a given moisture content. To do this, you just need to solve two simple mathematical examples. But what will be the weight of a beam of natural humidity 150x150x6000 mm? In order to determine this, among other things, you need to know the last indicator itself for a particular type of wood.

You can also obtain such information from special tables. So, for example, the natural humidity of pine is 60-100%, larch - 50-70%, birch - 70-90%. These parameters should be taken in this case to calculate the weight. In this case, for obvious reasons, it will be impossible to make accurate calculations.

So, how much does a beam of 150x150x6000 mm of natural humidity weigh? Taking into account the data in the table presented above:

pine beams of such dimensions will weigh from 580/7.4=78.3 (60%) to 730/7.4=98.6 (100%) kg;

the weight of larch timber with natural humidity 150x150x6000 mm will vary from 820 / 7.4 = 110.8 kg to 930 / 7.4 = 125.7 kg.

In a similar way, you can calculate beams of such natural moisture dimensions for any other rock.

Specific gravity

There are only two types of wood density:

volumetric weight (the density of the physical body of wood itself);

specific wood fibers directly).

Above we discussed a method for determining the volumetric weight of timber 150x150x6000. Natural humidity or specified in such calculations is an important indicator. Indeed, in this case, the weight also depends on the amount of moisture contained in the wood structure. But if desired, you can also calculate the specific density index for beams.

This can be done using the table presented above. Calculations in this case will be carried out without taking into account humidity. That is, to calculate, you need to find the number of beams of a certain size per cubic meter and simply divide the indicator from the table by the resulting number.

Thus, for pine 520 / 7.4 = 70.3 kg is the specific weight of the timber 150x150x6000. Natural humidity - permissible operational or any other - is not taken into account in this case.