Table measuring timber round timber 11 meters long. How to calculate the cubic capacity of round timber: basic methods

For industrial procurement round timber It is quite difficult to determine its cubic capacity. To accurately calculate the volume of each log, you can use the formula for the volume of a truncated cone, which takes into account the main diameters of both cuts and the length of the log itself.

Round timber is very convenient and practical for building houses, bathhouses and other residential and non-residential premises.

In fact, like this in a complicated way The cubic size of round timber is not calculated. It is accepted all over the world to be considered more in a fast way. Special tables are used for this.

How to calculate the cubic capacity of a single tree without additional measurements?

Just a few years ago, to calculate the volume of a single tree, they used the product of the arithmetic average of the area of ​​the cuts and the length of the tree. Using a meter (reminiscent of an ordinary caliper), the diameter of the tree in its middle part was determined. Then it was multiplied by 3 to obtain the cross-sectional area.

Next, the resulting number was multiplied by the length of the workpiece, and a volumetric result was obtained. This method of calculation is inaccurate, since the thickness of the bark is not taken into account. The number Pi was taken with a large deviation from the real one, and the formula in its distorted form gave large errors.

The formula itself looks like this: the diameter of a rounded log is divided by 2 and squared, then multiplied by Pi and the length of the log.

Even if you measure the thickness of the bark and take this into account to determine the diameter of the tree, deviations from real indicators will be inaccurate, although with a smaller error. More accurate calculations showed that the actual deviations in the calculations of the cubic capacity of a round log during primitive measurements have a certain dependence on the parameters of the tree, which was taken into account when compiling the corresponding tables to determine the volumetric parameter. Let's try to figure out how to calculate the cubic capacity of the forest. For this you will need:

• roulette;
• corresponding calculation tables, where there is a finite cubic capacity.

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?
Peculiarities .
How much does a cube of board weigh?

Technology for calculating the volume of a single log

First, you need to use a tape measure to measure the length of the tree and its diameter at the top of the cut (excluding the bark). After this, let's look at the tabular parameters: at the intersection of the line indicating the length of the tree and the column indicating the corresponding diameter, we find the volume of the measured body. Everything is simple and reliable.

Such calculations also cannot be called absolutely accurate, since the features in which the forest was grown and the shape of the trunk are not taken into account. But with large volumes of workpieces, it is customary not to pay attention to such trifles.

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Calculation of cubic capacity of stored timber

For industrial volumes of round logs, other techniques and tabular data are used. In essence, a round forest in a stored state has the shape rectangular parallelepiped. Calculations of its volume are familiar to everyone from school. But this method cannot be used, since the size of the voids between the logs will not be taken into account. By the way, they also directly depend on the diameter of the logs, which can be calculated mathematically.

Through numerous calculations, the coefficient was determined, with the help of which a special table was compiled. It works similarly to the previously described table, with the only difference being that the volume of the mentioned parallelepiped and the average thickness of the upper cut are taken into account. The cubic capacity of the forest can be calculated with great accuracy.

But one cannot hope for good accuracy of calculations when stacking forest products inaccurately. This procedure is not used when storing timber in a warehouse, since in this case the volume that round timber occupies directly in the warehouse is estimated.

It is very easy to calculate the cubic capacity after preliminary weighing of the forest.

Next, you need to calculate the volume by dividing the mass of the forest by the density, which corresponds to the type of wood. This calculation also cannot be considered ideal, since the forest has a deviation in density at different degrees of maturity. The moisture content of the wood can also play a special role here.

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• calculation of main equipment
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• cost of installation, commissioning, personnel training
• calculation of the cost of preparation of the production site
• calculation of the cost of production or waste disposal complex
• calculation of profitability of production or waste disposal complex
• return on investment calculation
The cost of settlements is determined after receiving an official request and generating a list and completeness of our services.

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• EQUIPMENT PRODUCTION: pellet/briquette lines, drying complexes, disintegrators, biomass presses
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We analyze future production from A to Z! We begin the study by calculating the volume of the raw material base, its quality, and supply logistics. Amounts of biomass per initial stage and its supply should be sufficient for the uninterrupted operation of the equipment long time. Based on objective information collected about future production, we calculate the characteristics of the main equipment, and, at the request of the customer, additional equipment and mechanisms.

The total cost of the project necessarily includes the costs of preparing the production site, installation and commissioning works, and personnel training. And in the forecast of production costs, energy efficiency and the specific cost of producing a unit are taken into account in advance finished products, its technical and quality characteristics, compliance with international standards, profitability and payback period. The use of equipment for the production of extruded feed significantly increases the profitability of livestock farming by improving their quality and reducing costs.

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The full range of engineering services provided by BM Engineering includes: drawing up a business plan for production with calculations of energy efficiency, profitability and cost of production, design, construction, commissioning, commissioning and service. In addition, the company supplies equipment own production, carries out work on automation and certification of constructed enterprises.

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In the first half of 2015 alone, 6 specialized seminars “Basics of Pellet Production” were held, at which about 200 students were trained. Since the second half of 2015, seminars have been held monthly and are becoming increasingly popular among students. Those specialists who listened to all the lectures and looked at the operating equipment completely changed their attitude towards pellet production technology. The wet pressing method is completely new innovative approach to biomass processing, which is the future.

If there are no problems with determining weight and volume, for example, when purchasing liquids or bulk materials, then with timber the situation is the opposite. Here, the system for determining the volume of the required quantity of a given raw material raises a lot of questions, because no one wants to pay extra money.

Instructions

1.

2. First, the measured batch of commercial slab should be sorted into 2 groups. One group consists of boards longer than 2 m, the other less than 2 m. Stacking is done with thick and thin ends alternately in different directions, while the surface of the slab remains at the bottom and at the top. The stack should be super-compact and tightly stacked at right angles and have an identical height.

4. The volume of lumber from coniferous and deciduous wood can be determined by two methods. The first method involves freezing the entire block or board, and then the volume, after which the results are summed up.

5.

6. Absolutely, it’s worth focusing separately on measuring the cubic capacity of a round forests. Here you have to measure each log separately - the length and width of the upper and lower ends. The special tables on which these calculations are made are called cubeturns, which were discussed above.

7. After the volume of the entire log has been measured individually, addition is performed and the total cubic capacity is obtained. Currently, a corresponding computer program already exists.

If there are no problems with determining weight and volume, for example, when purchasing liquids or bulk materials, then with timber the situation is the opposite. Here, the system for determining the volume of the required quantity of a given raw material raises a lot of questions, because no one wants to pay extra money.

Instructions

1. It turns out that not all clients realize how many types of wood actually exist. And tea differs from each other in the degree of processing, type, grade, which directly affects its cost. Here's how to calculate the volume of slab - a very popular type of lumber.

2. First, the measured batch of commercial slab should be sorted into 2 groups. One group consists of boards with a length of more than 2 m, the other - less than 2 m. Stacking is done with thick and thin ends alternately in different directions, while the surface of the slab remains at the bottom and at the top. The stack should be super-compact and tightly stacked at right angles and have an identical height.

4. The volume of lumber from coniferous and deciduous wood can be determined by two methods. The first method involves freezing each block or board, and then the volume, after which the results are summed up.

5. 2nd method - with the help of a cubeturner, a special table prepared for determining the volume of such lumber. Boards belonging to unedged lumber are measured in a slightly different way. IN in this case width of one-sided trim and unedged boards is calculated as half the sum of the upper and lower planes.

6. Undoubtedly, it is worthwhile to dwell separately on measuring the cubic capacity of round timber. Here you have to measure each log separately - the length and width of the upper and lower ends. The special tables on which these calculations are made are called cubeturns, which were discussed above.

7. After the volume of each log is measured separately, addition is performed and the total cubic capacity is obtained. Currently, a corresponding computer program already exists.

Video on the topic

16.06.2014 21:04

After all the ideas for implementing the construction of a house have been worked out and the final option for building a house from rounded logs has been selected, the question arises how much such a house will cost you. To determine cost of building a log house from rounded logs , you need to know how many cubes of logs are in this log house. In this article we will try to explain in detail how to calculate the cubic capacity for the construction of rounded logs.

Calculation of cubic capacity of rounded logs

The simplest way to calculate is using the formula - πr². H

Π — 3,14

r² — radius of a rounded log squared

N - length of rounded log

Substitute the data into the formula:

3.14 *(0.11 m)²* 6m= 0.228 m3

So, we got how many cubes are in one rounded log with a diameter of 220 mm. Next, you need to calculate the number of logs in your house and multiply the resulting amount by the cubic capacity of one log (0.228 m3). You can easily count the number of logs in a wall, but initially you need to determine for yourself how high the floor will be.

Calculating the cubic capacity of lumber is not an easy task, but necessary

It is also necessary to add 7% to the resulting height by shrinkage , if the log has natural moisture.

For example, the height of the first floor is 2.9 meters. The height of one log is 220 mm minus the lunar groove will be 190.5 mm. Next, we divide the floor height of 2.9 m by the thickness of the log without a groove - 0.19 m, having previously converted all the numbers into meters.

2.9: 0.19 = 15.26 pieces. We got required quantity logs with a diameter of 220 mm in order to build a floor 2.9 meters high. You must not forget to add 7% for shrinkage of the house. In total you will get 16 crowns. Now, to find out the full volume of the floor of a 6x6 house, 16 crowns high, you need to perform the following calculation:

16 (crowns) * 4 (walls) * 0.228 (volume of one log) = 14.6 m3 of logs. Now, to find out the cost of a rounded log for the entire log house, you need to multiply the number of cubes obtained by the price of the log for one cube. The cost of one meter of cubic rounded log can be found Here .

To perform calculations for other log diameters, we offer you a number of pre-calculated tables, using which you will certainly find answers to your questions.

Article prepared by the company ASK Egida , which performs construction of houses from logs and provides wide range of construction services in the suburban housing construction market.

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Methodology for calculating the mass and volume of logging residues

One of the tasks when developing a project technological regulations The process of handling construction and demolition waste involves calculating the mass and volume of logging residues generated during the cutting down of green spaces (tree removal) in the construction or demolition zone.

The official methodology for calculating the mass and volume of logging residues for these purposes in Russian Federation No. The initial data for such calculations is information about the trees being cut down (species, height and thickness at a height of 1.3 m) and shrubs (young trees), given in the count sheet from the composition project documentation to the construction (demolition) site.

This article presents a method for calculating the mass and volume of logging residues developed in our company. As the basis for its development, tabular data from the All-Union standards for forest taxation, approved by Order of the USSR State Forestry Committee of February 28, 1989 No. 38, was used.

1) Data from Table 17 “Volumes of trunks (in the bark) in young trees by height and diameter at a height of 1.3 m” - to determine the volume of trunks of young growth and shrubs.

Cube for round logs

As a result of processing the given data to determine the average ratio between the diameter (D), height (h) and volume (V) of one trunk, the calculated shape coefficient (Kp from Table 1) was determined, which with an accuracy of +/- 10% allows you to determine the volume of the trunk by formula Vst=Кn*h*пD2/4.

2) Data from tables 18 and 19 “Volumes of trunks (in the bark) of tree species by height and diameter at a height of 1.3 m with an average shape coefficient” - to determine the volume of trunks of various tree species. As a result of processing the given data to determine the average ratio between the diameter (D), height (h) and volume (Vst) of one trunk, calculated coefficients were determined for some of the tree species listed in the table, which with an accuracy of +/-10% allows us to determine the volume of the trunk according to the formula Vst = Кn*h*пD2/4. Estimated odds forms are given in table 1

3) Data from table 185 “Weight of 1 cubic meter. m and volume 1 t of wood different breeds" - to determine the mass of wood, the mass values ​​of one cubic meter of the corresponding wood species from the column “freshly cut” were used, or from the column “dry” - for dead wood.

4) Data from table 206 “Volume of bark, twigs, stumps and roots” to determine the volume of twigs and branches, as well as stumps and roots as a percentage of the volume of trunks. For the calculation, average values ​​from the interval given in the tables were used. The volume of twigs and branches is 7% of the volume of trunks, the volume of stumps and roots is 23% of the volume of trunks.

5) Data from Table 187 “Fully wooded brushwood and cottonwood coefficients” - to determine the folded volume of twigs and branches from the full wooded volume using a conversion factor of 10.

FKKO-2014 contains codes for the following waste:

1 52 110 01 21 5 Waste of twigs, branches, tips from logging

1 52 110 02 21 5 Stump uprooting waste

1 54 110 01 21 5 Low-value wood waste (brushwood, dead wood, trunk fragments).

Therefore, the calculation of the mass and volume of logging residues must be calculated by type of waste:

• trunks of trees, young growth and shrubs cut down according to the accounting list can be classified as waste of low-value wood (brushwood, dead wood, fragments of trunks);
• twigs and branches - to waste of twigs, branches, tips from logging;
• stumps and roots - waste from stump uprooting.

For the technological regulations of the Process of handling construction and demolition waste, it is necessary to calculate the mass of waste, but for temporary storage in storage bins and their removal from the construction site, it is necessary to estimate the volume of logging residues, and in the storage volume.

The calculation is made using the Excel application. An example of an Excel page table header is shown in Table 2.

The calculation was carried out in the following order:

1) Filling out the initial data according to the accounting sheet;

column 2 - line number of the accounting sheet;

column 3 - wood type;

column 4 - number of trees;

column 5 - minimum diameter trunk from the interval specified in the counting sheet;

column 6 - the only value of the trunk diameter indicated in the counting sheet;

column 7 - maximum trunk diameter from the interval specified in the counting sheet;

column 8 - minimum height trunk from the interval specified in the counting sheet;

column 9 is the only value of the trunk height indicated in the counting sheet;

column 10 - maximum height trunk from the interval specified in the counting sheet;

column 11 - additional number of trunks - if in the column “characteristics of the state of green spaces” n trunks for one tree are indicated, then in column 11 it is indicated (<значение графы 11>= (n-1)*<значение графы 4>.

2) Calculation of the average value of the trunk diameter if there is an interval:<среднее значение диаметра ствола (графа 6)> = (<значение минимального диаметра (графа 5)>+<максимальное значение диметра (графа 7)>)/2;

3) Determination of the volume of one trunk<объем ствола (графа 12)>is made according to Vst = Kn*h*пD2/4, where Kn is the corresponding shape coefficient from Table 1, D is the average trunk diameter, h is the average trunk height. Calculation of the volume of one trunk:<объем ствола в куб.м (графа 12)>=Кn* π*(<диаметр ствола в см (графа 6>/100)* (<диаметр ствола в см (графа 6>/100)*< высота ствола в м (графа 9)>/ 4);

4) Calculation of the dense measure of trunk volume Vpl=Vst*nst, where nst is the total number of trunks:<плотная мера объема стволов (графа 13)> = <средний объем ствола в куб.м (графа 12)>*(<число деревьев или кустов (графа 4)>+<число дополнительных стволов (графы 11)>). For one bush, the number of additional trunks is taken to be 5;

5) Calculation of folding measures (when storing or transporting, it is necessary to take into account the average volume of space occupied by tree trunks or bushes:<складочная мера объема стволов (графа 14)>= <плотная мера объема стволов (графа 13)>*4/p;

6) Calculation of the volume of twigs and branches depending on the volume of the trunk is carried out in accordance with paragraph d) of this article:<объем сучьев и ветвей в плотной мере (графа 16)> = <плотная мера объема стволов (графа 13)> *<переводной коэффициент (графа 15=0,007)>. In folding measure - according to paragraph e) of this article:<объем сучьев и ветвей в складочной мере (графа 18)> = <объем сучьев и ветвей в плотной мере (графа 16)>*<переводной коэффициент (графа 17=10)>;

7) Calculation of the volume of stumps and roots from the volume of the trunk is carried out in accordance with paragraph d) of this article:<объем пней и корней в плотной мере (графа 20)> = < плотная мера объема стволов (графа 13)>*<переводной коэффициент (графа 19=0,23)>. In the fold measure, the volume of stumps and roots is assumed to be double volume:<объем пней и корней в складочной мере (графа 21)> =<объем пней и корней в плотной мере (графа 20)>*2.

8) Calculation of the total volume of wood in a dense measure:<полный объем (графа 22)> = <объем стволов в плотной мере (графа 13)>+<объем сучьев и ветвей в плотной мере (графа 16)>+< объем пней и корней в плотной мере (графа 20)>;

9) Calculation of the total volume of wood in a folded measure (this indicator most objectively allows us to assess the need for the capacity of bodies (containers) vehicles for removal of logging residues):<полный объем древесины в складочной мере (графа 23)> = <складочная мера объема стволов (графа 14)>+ <объем сучьев и ветвей в складочной мере (графа 18)>+ <объем пней и корней в складочной мере (графа 21)>

10) The volumetric weight of wood in a dense measure (density in t/m3) is recorded in column 24 in accordance with paragraph c) of this article, for species not listed in table 185 - in accordance with Appendix 3 to SNiP II-25-80 (Density of wood and plywood ).

11) Calculation of the weight of the trunks:<вес стволов (графа 22)> = <объем стволов в плотной мере (графа 13)>*<объемный вес древесины (графа 21)>;

12) Calculation of the weight of twigs and branches:<вес сучьев и ветвей (графа 26)> = <объем сучьев и ветвей в плотной мере (графа 16)>*< объемный вес древесины (графа 24)>;

13) Calculation of the weight of stumps and roots:<вес пней и корней (графа 27)> = <объем пней и корней в плотной мере (графа 20)>*< объемный вес древесины (графа 24)>;

14) Total weight exported waste (logging residues):<вес вывозимого отхода (графа 28)> = <вес стволов (графа 25)> + <вес сучьев и ветвей (графа 26)>+<вес пней и корней (графа 27)>

Thus, the proposed methodology allows you to calculate the volume (both full and folded) and weight of logging residues, differentiated by type of waste based on the initial data of the counting sheet, as well as estimate the required volume of storage bins or vehicle bodies and the number of vehicle trips for their removal.

K.Nikonenko

There is no point in making the same calculations several times if the source data does not change. A rounded log with a diameter of 20 cm and a length of 6 meters will always have the same volume, regardless of who is doing the counting and in which city. Only the formula V=πr²l gives the correct answer.

How to calculate forest cubic capacity

Therefore, the volume of one central bank will always be V=3.14×(0.1)²×6=0.1884 m³. In practice, in order to exclude the moment of standard calculations, cubatures are used. Such useful and informative tables are created for various types lumber. They help to save time and find out the cubic capacity of round timber, boards, central fiber boards, and timber.

1. Roundwood cubature
2. How to use the table?
3. Product capacity of different sizes

What is a cubical?

The name of this construction guide is due to the fact that the volume is physical quantity measured in cubic meters (or cubic metres). For a simpler explanation, they say “cubature”; accordingly, the table was called “cubature”. This is an ordered matrix that contains data on the volume of one product for various initial parameters. The base column contains sections, and the row contains the length (molding) of the material. The user just needs to find the number located in the cell at their intersection.

Let's consider concrete example- round timber cube. It was approved in 1975, called GOST 2708-75, the main parameters are diameter (in cm) and length (in meters). Using the table is very simple: for example, you need to determine the V of one log with a diameter of 20 cm and a length of 5 m. At the intersection of the corresponding row and column, we find the number 0.19 m³. A similar cubature for round timber exists according to a different standard - ISO 4480-83. Directories are very detailed in increments of 0.1 m, as well as more general, where the length is taken in 0.5 m increments.

Little secrets

Using the cubeturner itself is not difficult, but main nuance– correct data. Round timber is not a cylinder, but a truncated cone, in which the lower and upper cuts are different. One of them may be 26 cm, and the other 18. The table assumes a clear answer for a specific section.

Various sources suggest doing it in two ways: calculate the average value and take the volume from the reference book for it, or take the size of the upper cut as the main section. But if the tables were compiled according to certain standards, then they must be used in accordance with the accompanying instructions. For the cubature GOST 2708-75, the diameter of the top cut of the log is taken. Why is the moment of initial data so important? Because with a length of 5 meters for Ø18 cm we get 0.156 m³, and for Ø26 cm – 0.32 m³, which is actually 2 times more.

Another nuance is the correct cubatures. If in the GOST 2708-75 table complex formulas for truncated cones were used, calculations were carried out, and the results were rounded to thousandths, then modern companies that compose their own cubes take “liberties”. For example, instead of 0.156 m³ there is already the number 0.16 m³. Quite often, websites on the Internet contain frankly erroneous cube-turners, in which the volume of a log 5 meters long with a diameter of 18 cm is indicated not as 0.156 m³, but as 0.165 m³. If an enterprise uses such directories when selling round timber to consumers, then it makes a profit, actually deceiving customers.

After all, the difference on 1 product is significant: 0.165-0.156 = 0.009 or almost 0.01 m³.

The main problem of round timber is the different cross-section. Sellers offer solutions to settlement issues in the following ways:

• calculating the volume of each unit and summing the obtained values;
• storage method;
• finding the average diameter;
• method based on wood density.

It must be said right away that the first of these options gives the correct results. Only calculating the volume of each log and then adding up the numbers guarantees that the buyer will pay for the timber that he receives from the company. If the length is the same, then it is enough to find the cross-sectional areas of all the trunks, add them up, and then multiply by the length (in meters).

2. Storage method.

It is assumed that the stored round timber occupies a part of the space shaped like a rectangular parallelepiped. In this case, the total volume is found by multiplying the length, width and height of the figure. Considering that there are voids between the folded trunks, 20% is subtracted from the resulting cubic capacity.

The downside is accepting as an indisputable fact that the tree occupies 80% of the total space. After all, it may well happen that the beams are folded inaccurately, thereby the percentage of voids is much higher.

3. Density based method.

In this case, you need to know the mass of the forest and the density of the wood. The cubic capacity is easily found by dividing the first number by the second. But the result will be very inaccurate, since wood of the same type has different densities. The indicator depends on the degree of maturity and humidity.

4. Average method.

If the trunks of harvested trees are appearance almost identical, then choose any 3 of them. The diameters are measured and then the average is found. Next, using the cubature, the parameter for 1 product is determined and multiplied by the required quantity. Let the results show: 25, 27, 26 cm, then Ø26 cm is considered average, since (25+26+27)/3=26 cm.

Considering the disadvantages of the considered methods, the only the right way The calculation of cubic capacity can be considered by finding the volume of each log using a cubic meter GOST 2708-75 or ISO 4480-83 and summing up the data obtained.

Calculation of cubic capacity of lumber - count correctly

During the construction of wooden structures, various lumber is purchased.

When buying or selling it, there is a need to measure it. All the complexity of measuring lumber due to its fickleness and custom size and shape, weight and quality. It is also impossible to sell such a product individually due to the factors mentioned above. Make it right calculation of lumber cubic capacity It is very difficult for a non-specialist, and even regulatory authorities are sometimes unable to verify whether the calculation was performed correctly.

Some lumber from the manufacturer is supplied in packages indicating the exact volume and cost. But this practice is quite rare. In addition, consumers may have doubts about the correctness of the calculation of the cubic capacity of lumber, as well as about the indicated price. The average buyer does not always know that in addition to cubic capacity, the cost of lumber depends on the degree of processing, that is, unedged or edged boards, wood species and grade. In addition, the cost of boards up to 1.7 m long is lower than the cost of more long boards. The quality of manufactured lumber is regulated by a huge number of rules and regulations, technical specifications and others regulatory documents, which individual developers are not even aware of, while at the same time, lumber sellers are in no hurry to familiarize their customers with the rules for selling lumber. In order to have at least a general idea of ​​how the cubic capacity of lumber is calculated, it would not be amiss to familiarize yourself with the rules for measuring some of their most common types.

According to current regulations, croakers must be sorted depending on their length into two groups - up to two meters and over two meters. The slab is stacked, alternating thick and thin ends, as well as the slab surface. The stacks must be the same height along the entire length, right angles, and they must be stacked as tightly as possible. Then, by multiplying the width, length and height of the package, the folded cubic capacity is obtained.

Calculation of cubic capacity of round timber

Volume of 10 m of softwood beams, m³

In the woodworking industry, there are concepts of folded and dense cubic meters. The price list for lumber is indicated for volume in a dense mass, therefore folded cubic meters must be converted into a dense mass. For this purpose, special conversion factors are used. For example, for a slab up to two meters long, a coefficient of 0.48 is used, and for a slab more than two meters long - 0.43.

There are two ways to determine the volume of lumber of softwood and hardwood. Either by measuring each unit of material, or using a special standard, or cubic meter, established by GOST and intended to determine the volume of edged sawn hardwood and coniferous species. The standard contains a table of one unit of lumber and a table of the volume of a meter, based on which you can calculate the cost of lumber.

When calculating the cubic capacity of unedged lumber, slightly different rules apply.

How to accurately calculate the cubic capacity of a log?

The specificity of their measurement is that the width of one-sided and unedged boards is calculated as half the width of two layers - narrow and wide, which are measured in the middle of the board. The volume of round timber is calculated based on the measurements of each log. Density cubic meters of logs are calculated using the corresponding GOST, which indicates the volumes of round timber. These volumes are measured by the length of the log and the thickness of the upper end.

The table we offer shows calculation of lumber cubic capacity: edged and unedged boards, floor boards, timber, timber, lining and slats. Using the table, you can calculate the amount of lumber in 1 m3.

The purpose of this article is to explain to you how to correctly calculate the area of ​​the walls of log houses, bathhouses and other buildings, as well as buildings made of laminated and corrugated timber. Many will say - What is there to explain and everything is clear - you just need to know the basics of geometry.

Round timber cubator - how to calculate the volume?

Absolutely right - you can’t do without geometry, but this measurement has its own peculiarity, unlike walls made of timber and other materials, but more on that below.

Why you need to know how the area of ​​log houses is calculated:

• will help you more accurately calculate the cost and quantity of required material*
• Calculate the cost of painting and sanding the logs yourself

To calculate the area of ​​walls, we all know that we must know two quantities - height and length, and for a complete calculation, the area of ​​​​the ends as well
S=Pi*R2 - area of ​​1 circle (end),Where
Pi — 3,1428
R— end radius
Knowing the area of ​​one end, we multiply this value by the number of ends and get total area ends.
Main feature log buildings is that the logs have a convex shape, so the height measured as usual - from floor to ceiling will differ from the actual one by 10-15%.

photo #1
photo No. 2

We calculate the area.

To measure the height of one log, you just need to take a tape measure and lay it down from the top seam to the bottom seam of the crown as shown in photo #1(To measure the height of a log house from a chopped log, the average value is taken). And for a beam you need to measure the width of the edges and add it to the value A(arrows shown on photo No. 2). We will get the real height of one log or beam, and knowing the number of crowns, we will get the real height of the wall (number of crowns * height of one crown). I don’t think it’s worth reminding you of the formula for the area of ​​a rectangle. It's that simple.

Photo No. 4.

And so, adding up all the data - the area of ​​​​the walls, "triangles", ends and from the resulting amount subtract the area of ​​​​windows and doorways— we will receive the full area of ​​the building and, based on this data, we will be able to independently calculate (knowing the price of work per m2) the cost of work, materials*, as well as their volume* (by transferring them to the company manager by phone or by coming to the office)**.

I'll give you one last thing little advice, if by measuring the structure of a simple form everything is simple and does not amount to a lot of work and will not require much time, but what about complex forms, such as photo No. 4.

photo No. 4

I’ll tell you straight - take the measurements yourself or be present at the measurements when your workers do it, this way you will avoid being deceived by unscrupulous construction crews or contact trusted companies.

*the cost and volume of the required material (coating) is affected by the condition of the wood (sanded, not sanded) and the method of applying the coating (brush, roller, spray)

**for your convenience, on our website, the cost of materials is calculated per 1m2

Still have questions? Call

(A. Sokolov, Terem Grad)

Construction work requires solving many different issues, among which the most important task is the selection and purchase of lumber. Calculate how much linear meters boards and timber will be needed during the construction process, it’s not difficult. But the price of industrial wood is indicated per 1 cubic meter, and this often causes difficulties for novice home craftsmen. The ability to correctly select and calculate the amount of edged or unedged lumber in a cube will allow you to save money and avoid a situation where, after completion construction work There is a pile of unused boards left on the site.

Classification and characteristics of lumber

The very name “lumber” suggests that this type of construction raw material is obtained by longitudinal sawing of tree trunks on circular or band saws. Several cutting methods are used to produce boards and timber:

• tangential (in a circle),
• radial.

Tangential cutting involves moving the saw tangentially to the annual rings of the tree, which reduces the amount of waste and, therefore, reduces the cost of building materials. The boards obtained in this way have a beautiful, pronounced pattern, therefore they are often used for finishing purposes. Disadvantages of circular sawing include the tendency of the wood to shrink and swell, as well as a significant difference in texture as it approaches cutting tool to the center of the log.

In the sawmill industry, several methods are used for sawing a trunk.

With radial sawing, the cutting line passes through the core of the tree, so the yield of boards will be smaller, and their price will be higher. However, if necessary, obtain wood high quality use exactly this method. This is due to the fact that, compared to the tangential method, radial sawing boards have halved swelling and shrinkage rates. In addition to the cutting methods discussed above, a mixed method is also used, which combines the advantages of the first two.

The concept of lumber actually includes not only the traditional moldings that are most often seen in construction markets. The full list of products obtained from sawing logs includes:

• board;
• beam;
• bar;
• lagging;
• croaker

The last two types of lumber are classified as waste, which absolutely does not prevent them from being used for certain types of construction work, as well as for finishing purposes.

Boards

Boards include rectangular lumber with a thickness of no more than 100 mm and a width to thickness ratio of at least 2:1. Depending on the degree of processing, the board can be edged or unedged. The first is finished product without bark and with smoothly sawn edges, while the second is a “semi-finished product”, removed directly from the saw frame.

The edged board has smooth edges and a constant width along the entire length of the lumber

The most commonly used boards in construction are the following standard sizes:

• thickness - 25 mm, 40 mm, 50 mm, 60 mm;
• width - from 75 to 275 mm with gradation every 25 mm;
• length - from 1 m to 6.5 mm in increments of 250 mm.

Boards of other sizes can be obtained by trimming or planing standard lumber, as well as by placing an individual order for sawing round timber.

Unedged boards have a lower cost, but without finishing its scope of application is limited

The parameters of lumber used in construction are standardized and determined according to the current GOST 8486–86 for coniferous wood and GOST 2695–83 for hardwood.

timber

Timber is lumber whose cross-section is a square with sides of at least 100 mm. The diameter of the timber is unified and can vary from 100 to 250 mm in increments of 25 mm. The standard defines the length of products of this type from 2 to 9 m, but most often square-section lumber with a length of no more than 6 m is used. In some cases, products with a cross-section of 150x100 mm, 200x100 mm or 200x150 mm, which according to the existing classification are much closer, are mistakenly classified as timber to the sleepers.

Timber is an ideal material for the construction of frames and other wooden structures

The bar differs from the beam discussed above only in that its cross-section does not exceed 100x100 mm. The typical length of the bar is also 6 m, and the diameter ranges from 40 mm to 90 mm in increments of 10 mm. To simplify the classification, bars are often classified as slats with a rectangular cross-section and a thickness-to-width ratio of at least 1:2. The standard range of edges for softwood slats looks like this: 16, 19, 22, 25, 32, 40, 44, 50, 60, 75 mm. For hardwood lumber, products of increased width are additionally provided, and the product line itself looks like this: 19, 22, 25, 32, 40, 45, 50, 60, 70, 80, 90, 100 mm.

A variety of bars and slats allow you to strengthen and make any wooden structure as stable as possible.

Obapole and croaker

Obapol is the very first cut of a round timber, the outer surface of which remains untreated. Unlike obapol, croaker can have a cut on half of the second side or alternating treated and untreated areas on the bark side. The importance of obapole and slab in construction is secondary, since the unaesthetic appearance and reduced performance characteristics allow the use of lumber of this type only for auxiliary purposes. Most often, croaker and obapol are used as fastening material, as well as for the manufacture of formwork, lathing or flooring scaffolding. This material is also interesting in quality decorative material for decorating walls, fences and other vertical structures.

Despite their external ugliness, croaker and obapole are widely used for minor construction tasks

Technology for calculating the number of boards in a cube

The wood market offers both edged lumber and unedged boards, with wane remaining at the edges. Depending on the type of wood products, several methods are used to determine cubic capacity.

How to find out the number of edged lumber in a cube

The algorithm for determining the cubic capacity of lumber is based on the formula known to every schoolchild for finding the volume of a rectangular parallelepiped. In order to find out the cubic capacity of one board (V) per cubic meter. m, you need to find the product of its length (a) by its width (b) and thickness (h) in meters V=a×b×h.

The desired figure will make it easy to calculate how many boards of this type will fit in one cubic meter lumber. For this, 1 cu. m of lumber is divided by the volume of one product. For example, if you need to find out the cubic capacity of one board with parameters 6000x200x25 mm, then by substituting these numbers into the formula, we get V = 6x0.2x0.025 = 0.03 cubic meters. m. Consequently, in one cubic meter there will be 1/0.03 = 33.3 such products.

A tongue and groove board has a groove on one side and a tongue on the other. Since both of these elements are approximately equal to each other, their parameters can be neglected. That is why the cross-sectional size of tongue-and-groove lumber is measured without taking into account the locking part.

In the case of boards that have the same dimensions, the calculation can be simplified by substituting the dimensions of the lumber stack into the formula. Of course, its installation should be as tight as possible, otherwise the gaps between the individual elements will affect the accuracy of the calculations. Considering that the cost of individual types of wood reaches tens of thousands of rubles, such an error can cost a pretty penny.

To simplify calculations, you can use special tables that allow you to quickly determine the cubic capacity or the amount of wood in 1 cubic meter. m of lumber.

Table: number of edged boards in 1 cubic meter. m of standard length lumber

The cubic capacity of timber of standard sizes can also be determined using the table below.

Table: amount of timber in 1 cubic meter. m of lumber

Very often it is necessary to determine the surface area (floor or wall) that can be covered with a board of one thickness or another with a volume of 1 cubic meter. m. To do this, you can use the formula S = 1/h, where h is the thickness of the lumber. So, one cubic meter of 40 mm board will be enough to arrange S = 1/0.04 = 25 square meters. m of floor. To facilitate the process of calculating the area, a table called a cubeturner allows you to simplify the process of calculating the area. It contains data on the cross-section of the boards, their number in 1 cubic meter. m and the required area that they can cover.

Method for calculating the cubic capacity of an unedged board

Unedged lumber is not trimmed at the edges, so not only the cross-sectional size of individual products varies, but also the width of different parts of one board. In this regard, it is possible to calculate the volume of a stack of unprocessed lumber only approximately. The same applies to calculating the cubic capacity of individual unedged lumber, although the error in this case will be much smaller.

So, to calculate the cubic capacity of an unedged board, there are two constant quantities - thickness and length, and one variable - width. To avoid complex calculations using differential algebra methods, the last parameter is simply averaged. To do this, the board is measured in several places and the arithmetic average is found. For example, for a board with a diameter of 400 mm at the base, 350 mm in the middle and 280 in the top, the calculated value will be (430+340+260)/3=343 mm. Further calculations are carried out in exactly the same way as for edged lumber.

Most often, the width of an unedged board is determined only on the basis of measurements along the edges of the lumber. It should be noted that the accuracy of calculations directly depends on the number of measurements, so in critical cases their number is increased.

If you need to find out the cubic capacity of a package of unedged wood, then the products are stacked on top of each other in such a way that the following conditions are met:

• the stacks must be aligned along the front end;
• boards in a stack should not be stacked overlapping;
• It is not allowed to change the width of the package along the entire length of the lumber;
• the protrusion of the outermost products beyond the stack should not exceed 100 mm.

By measuring the height, length and width of a package of unedged wood with a tape measure, the approximate cubic capacity is determined using the formula V=a×b×h. To find out a more accurate value, the result obtained is multiplied by the stacking coefficient, which can be found in special tables.

For many builders, the topic of calculating the number of logs in a cube is familiar. But for an unprepared person this may seem not only very distant, but also incomprehensible. And very often disagreements arise between the builders themselves, as well as between the builders and the customer, about how many logs there should be in a cube.

In order to deal with this problem, a mathematical method is usually used, which in a few minutes can give a clear answer about how many logs are needed for a certain number of cubic meters.

Typically in construction wooden buildings rounded logs are used. But this material may differ in size, that is, in length and diameter. The unit of measurement is usually centimeters. There are one million centimeters in one cubic meter. Thus, first you need to decide on the size of the logs.

In order to measure the size of the logs, you will need a regular centimeter tape measure. All logs, as a rule, should initially be the same size, and later, depending on the project, they are sawn into the necessary elements.

So, by measuring the size of a log using a tape measure, we obtain the length and diameter in centimeters. For example, let's try to calculate how many logs are needed for one cubic meter, if the logs are six meters long and their diameter is eighteen centimeters.

To calculate, you will need the following formula:

Volume = Pi * Radius * Radius * Length.

Six meters in this case equals six hundred centimeters. Pi is always 3.14. We get the radius by dividing the diameter by two. Thus, our formula takes the following form: Volume = 3.14 * (18:2) * (18:2) * 600 = 3.14 * 9 * 9 * 600 = 152604 centimeters. To convert to cubic meters, divide the resulting number by one million: 152604: 1000000 = 0.1526. This result tells us that one log of this size will occupy only a little over 0.15 cubic meters.

Now you need to figure out how many logs are in a meter. This is our main task. To do this, we divide one cubic meter by the result of our calculations - 0.1526. It turns out: Quantity = 1: 0.1526 = 6.55 logs. It turns out that for one cubic meter we need to take about seven logs of a given size.

If we consider logs of larger diameter, for example, twenty-four centimeters, then the calculation results will be different:

Volume = 3.14 * 12 * 12 * 600 = 271296 cubic centimeters = 0.2713 cubic meters.

This means that in one cubic meter there will be: 1: 0.2713 = 3.69 logs. In this case, there will be fewer logs in one cubic meter.

To calculate the number of logs per cubic meter, a very simple formula is used, which allows you to calculate the result in a matter of minutes. For calculations, of course, it is better to arm yourself with a tape measure and a calculator.