When round timber is being harvested, first of all they try to accurately calculate its cubic capacity.
Measurement is made at the top cut, where the diameter will be slightly smaller. When measuring trunks that have a cross-section different from a round one, they try to measure along the narrowest cross-section, passing through the center of the annual rings of wood.
This technique is used because it allows you to most accurately estimate how much of one log will get edged lumber, which has the greatest value in woodworking. Obviously, they will be cut based on the diameter of the top cut.
For the same reason, they prefer to discard the ridged part of the trunk, where the difference between the larger and smaller diameters of the cut is large, and not use it in the workpiece. All the same, the sawmill will accept the wood at the upper cut.
When determining the length, measurements are made with an accuracy of 10 cm, while the length is rounded down. This accuracy is due to the fact that when felling logs, usually two cuts are made - one higher, the other lower. First, they make the lower one, then the upper one - on the other side. falls in the direction where the top of his head is leaning. The cuts are made so that the lower one is on the side where the trunk should fall.
In this case, the upper cut is made on the other side, standing in the opposite direction to the most likely fall. During the subsequent sawing of the whip, they usually saw one cut with a saw, however, a cut error is often allowed - it can go a little obliquely, because of this there is such a large error.
Calculation by cubature
In accordance with it, it is possible to determine the volume of each log by making measurements and choosing the value according to the table. In the table, the diameter of the barrel goes in increments of 1-2 cm, and the length is 10 cm. Of course, it is not very convenient to use the entire cubature table.
This table provides data for the most common topsum diameters and lengths. Usually it is required to calculate the volume for logs up to 6 meters long. It is logs of this length that fit into most of the standard bodies of ordinary ones, not specialized as timber trucks or timber trailers for tractors, it is precisely in the size of up to 6 meters that logs are cut.
Naturally, when the timber is handed over to the sawmill, we are not talking about any "approximate" calculations, and it is necessary to apply the full GOST in the final calculation - after all, these are sawmills and the money of foresters who like accurate counting.
Formula calculation
V = πd²l / 4, where d is the trunk diameter in the upper cut, l is the length of the log, π = 3.14 - for our calculations, greater accuracy of this constant is not needed.
It is convenient when there is no GOST at hand, but only. With large volumes of work, even from three or four machines, it will take a lot of time to calculate in this way, in addition, this technique is not standardized and is not an argument in financial disputes.
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Almost everything in our world has its own dimension. We measure oil in barrels, coal in tons, the population of countries in thousands, millions.
We take as a basis a quantity that can specifically designate the object that we are measuring. When the question arises of how to calculate the cubic capacity of a board, we are no longer talking about the mass of the object, since wood has a completely different density, and one tree is different from another. In addition, boards of the same species will have different weights based on their moisture content.
For the convenience of calculating the cubic capacity of the board, volume measurement formulas are used.
It is enough to recall school mathematics and the necessary formula by which the width, length and height should be multiplied. For the calculation to be correct, it is necessary to adjust all parameters to one value, for example, in centimeters or decimeters. It is most convenient to take meters as a basis. Thus, having made three times the multiplication in meters, we get m³ or cubic capacity.
Note. To calculate the cubic capacity of the board, special formulas are used.
Cubic capacity of boards
Boards can vary in width, length, thickness. In addition, they are sold unedged and edged. Often, lumber has its own generally accepted standards that facilitate the calculation of cubic capacity.
For the usual sizes of material, there are already calculated volumes, which are systematized in tables for measuring the cubic capacity of boards. Therefore, to determine the volume of the material, you just need to open the table with the indicated dimensions and calculate the volume.
But, in order to do this, you must have these tables with you. Otherwise, in the absence of such, the cubic capacity of the edged board is calculated, before determining the thickness and length. These are the main dimensions that meet the requirements for sawn timber. They are different for each individual material. For example, to create a lathing, a board is used, in which the thickness is 25 mm, and for rough floors, 50 mm. Next, you need to measure the width of the board.
In the case of an edged board, everything is simple, since the material is trimmed in order to give the same width. Further, using a calculator, all values are multiplied among themselves. With a board length of 5 m, a thickness of 50 mm and a width of 25 cm, the volume of material will be:
5 x 0.050 x 0.25 = 0.0625 m³
After multiplying the resulting number by the number of boards, we get the total volume of material.
The formula for calculating the cubic capacity of the boards
V = L x h x b
L - length
h - height
b - width
Determination of the number of boards per cubic meter
1 m 3: V = N
In order to determine the cost of a specific type of board, with known values of volume: V x price 1 m 3.
There is one more point that you need to pay attention to when determining the cubic capacity of the boards - the nominal length is exactly 6.1 - 6.2 m, but this is not taken into account when selling. This often matters when buying a lot of material. For example, let's take a board with dimensions 150 x 20 mm.
Having made some simple calculations, we get the number of boards in 1 m 3 - 55, 5 pieces. So, in the cubic capacity of 6 m boards, there are exactly 55 pieces, in total, when calculating, we get a value of 0.99 m 3. Essentially, the overpayment for the cubic capacity of the board will be 1% of the exact price. For example, at a cost of 4,995 rubles, we pay 5,500 rubles.
Unedged board
Calculation features
The calculation of the cubic capacity of an unedged board is somewhat complicated, since the material does not have the same width between different boards, but also in each board separately. This can be explained quite simply - the tree does not have the same diameter.
It is clear that at the bottom it is wider, at the top it is narrower. Thus, the width of the edged board does not fall under any standards. What to do in this case? Use different formulas for the calculation. The width of the board is measured for convenience in the middle of the length. This gives you an average width. This counting method works well if the batch is small.
For industrial volumes
This method is not suitable, since the work will be very slow, and this is not profitable. For such cases, experts have developed the so-called unedged board cube. The volume in it is obtained by measuring and experimenting, in other words, by using many measurements and calculating the average value of the width.
Of course, this cannot be called a super accurate method, but the deviations are so small that they should not be paid attention to.
Some wood processing companies use the stack measurement method in practice. This does not require pre-sorting the wood by width. Experts measure the length of the board, the average width and height of the stack. The obtained values are multiplied among themselves, and the result is multiplied by the coefficient for calculating the cubic capacity of the board, which has an average value of 0.67.
Weighing method
In order to measure the cubic capacity of an unedged board, having obtained the most accurate result possible, the weighing method is used.
Before doing this, it is necessary to measure the moisture content of the material and dense wood. Considering that edged board is the cheapest material used in facilities with the least degree of responsibility, complicated calculations are not very justified.
Also, you should take into account that the result that you get will not be very different from the one that can be obtained using a cubic meter.
When erecting residential buildings
Here, professionals in their field are required to perform many tasks, including: calculation and budgeting before finishing the premises. In addition, you need to calculate the required amount of building materials. It is worth noting that this task is quite difficult. With this in mind, determining the cubic capacity of the board is an important point.
Note. The cubic meter of lumber is calculated using a single method. The type of board does not affect the result obtained.
To non-grooved species wood include: edged board, unedged board.
Grooved views- these are those that have special grooves for perfect joining of boards: flooring, lining,. Please note that when purchasing a grooved board, the calculation is carried out using the working width of the material, without spikes.
Regarding the calculation of the cubic capacity of an unedged board, with values of the width of one end of 25 cm, and 20 cm of the other, the average value will turn out to be 22 cm.To calculate a large amount of material, it is laid out in such a way that the wide part does not differ from the narrow one by more than 10 centimeters.
The main length of the board in the unfolded pack should be approximately the same. Then, using a tape measure, measure the height of the stack of boards and the width in the middle. The result, which is obtained from measurements, is multiplied by a coefficient with a value of 0.07 - 0.09, which depends on the air gap between the boards.
Buying materials by eye is nonsense, and no self-respecting owner will do this. In order to correctly draw up an estimate and estimate how much construction or major repairs will result in, you need to determine how much of this or that product will be needed. It is more difficult with boards - they are not sold by the piece, but released (as well as stocked) in batches, the volume of which is expressed in m³. But the number of pieces, as a rule, is "tied" to the area to be covered, that is, to m². Let's figure out how to determine how many boards there will be in one cube.
Why boards are exactly 4 and 6 meters? The calculation methodology given below does not change for any of their lengths. The fact is that the indicated parameters are the most "popular" ones. Manufacturers are guided by the dimensions of platforms and freight cars, so it is more profitable for them to supply boards with a length of 6 m. But the buyer is more interested in boards of four meters in length, since a truck with an elongated body is enough for their transportation.To transport 6 meter boards, you need a road train; This means that the cost of delivering lumber to the site will increase. And the maneuverability of such a transport is significantly limited. For example, it makes no sense to deliver boards on it to a suburban area, given the narrowness of the lanes.
The procedure for calculating the number of boards in a cube
You just need to remember high school. The so-called "cube" (the common name for a measure of volume) is the product of the linear parameters of any volumetric object. That is, its length, width and height (in this case, thickness).
- A measurement is made of the edges of one of the boards in a stack. It turns out the width and thickness. The length is known - 4 or 6 m.
- All measured parameters are converted into one dimension. Since we are talking about a cube, that is, m3, then all of them (including width and thickness) are indicated in meters.
- The "cubic capacity" of the workpiece is determined.
- 1 m³ is divided by the obtained value. The result is the number of boards per cube.
The numerator of the fraction does not have to be exactly 1. Planks are stored in different ways, and lumber in such an amount is not always required. If there are 0.8 cubic meters in a stack, then this is its volume.
Example. A board is bought 6 m, by 25 mm, 20 cm wide, in the amount of one cube.- We convert the values into meters: thickness - 0, 025, width - 0.2.
- Determine the cubic capacity of the board: 6 x 0.2 x 0.025 = 0.03 m³.
- We calculate the number of samples - 1: 0.03 = 33, (3).
Calculator for calculating the amount and volume of lumber
If the received value is fractional, then the result is always rounded to the nearest whole value. That is, only the numbers in front of the comma are taken into account. This is the accepted norm!
These tables will help you determine the approximate number of boards in a cube, without resorting to calculations.
- The calculation algorithm is the same for all sawn timber of this group, regardless of their characteristics - wood type, degree of drying.
- The tabular values are purely indicative, since they do not quite correctly reflect the real number of boards in a cube. Firstly, a lot depends on the stacking, that is, how tightly the boards fit. Secondly, nothing is said about the quality of workpieces processing (whether they are edged or not). Thirdly, it is not a fact that upon careful inspection a certain number of boards will not be rejected due to detected defects. Therefore, it is always necessary to slightly reduce the number obtained by calculation. If the board is edged - by about 10%, in the case of unedged - by 15 - 20%.
If there are no problems with the determination of weight and volume, for example, when buying liquids or bulk materials, then the opposite is true with timber. Here the system for determining the volume of the required amount of a given raw material raises a lot of questions, from the fact that no one wants to pay extra money.
Instructions
1.
2. First, the measured batch of business slab should be sorted into 2 groups. One group is made up of boards longer than 2 m, the other - less than 2 m. Stacking in a pile is made with thick and thin ends alternately in different directions, while the surface of the slab remains at the bottom and top. The stack must be super compact and tightly stacked at right angles and of the same height.
4. The volume of coniferous and deciduous sawn timber can be determined by two methods. The 1st method provides for the frozen entire bar or board, and then the volume, after which the results are summed up.
5.
6. It is absolutely worthwhile to dwell separately on measuring the cubic capacity of a round forests... Here it is possible to measure each log separately - the length and width of the upper and lower ends. Special tables on which these calculations are made are called cubes, which were discussed above.
7. Later, after the volume of the entire log is measured separately, addition is performed, and the total cubic capacity is obtained. Currently, there is a corresponding computer program more closely.
If, for example, there are no problems with the determination of weight and volume, for example, when buying liquids or bulk materials, then the opposite is true with timber. Here the system for determining the volume of the required amount of a given raw material raises a lot of questions, from the fact that no one wants to pay extra money.
Instructions
1. It turns out that in the distance, not all customers have an idea of 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 the slab volume is calculated - a hefty type of lumber in demand.
2. First, the measured batch of business 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 in a stack is carried out with thick and thin ends alternately in different directions, while the surface of the slab remains at the bottom and top. The stack must be super compact and tightly stacked at right angles and of the same height.
4. The volume of sawn timber made of coniferous and deciduous wood can be determined by two methods. The 1st method provides for the freezing of any bar or board, and then the volume, after which the results are summed up.
5. Method 2 - with the help of a cubature, a special table prepared for determining the volume of such sawn timber. The measurement of boards related to unedged sawn timber is made in a slightly different way. In this case, the width of one-sided edged and unedged boards is calculated as half the sum of the upper and lower planes.
6. It is unconditional that it is worthwhile to dwell separately on the measurement of the cubic capacity of round timber. Here it is possible to measure each log separately - the length and width of the upper and lower ends. Special tables on which these calculations are made are called cubes, which were discussed above.
7. Later, after the volume of each log is measured separately, addition is made and the total cubic capacity is obtained. Currently, there is a corresponding computer program more closely.
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16.06.2014 21:04
After all the ideas for the implementation of building a house have been worked out and the final version of building a house from a rounded log has been chosen, the question arises how much such a house will cost you. To determine the 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 a rounded log.
Calculation of the cubic capacity of a rounded log
The easiest way to calculate is by the formula - πr². H
Π — 3,14
r² - the radius of the rounded logs squared
H - the length of the rounded log
We 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 how many logs are in your house and multiply the resulting amount by the cubic capacity of one log (0.228 m3). It is easy to calculate the number of logs in the wall, but initially you need to determine for yourself what height the floor will be.
Calculation of the cubic capacity of lumber is not an easy task, but it is necessary
It is also necessary to add 7% to the obtained height by shrinkage if the log is of natural moisture.
For example, the height of the first floor is 2.9 meters. The height of one log 220 mm minus the lunar groove will be 190.5 mm. Next, we divide the floor height of 2.9m by the thickness of the log without a groove - 0.19m, having converted all the numbers into meters in advance.
2.9: 0.19 = 15.26 pieces. We received the required number of logs with a diameter of 220mm in order to build a 2.9 meter high floor. It is necessary not to forget and add 7% for the shrinkage of the house. The total is 16 crowns. Now, in order to find out the total volume of the floor of a 6x6 house, with a height of 16 crowns, you need to perform the following calculation:
16 (crowns) * 4 (walls) * 0.228 (volume of one log) = 14.6 m3 of a log. Now, to find out the cost of a rounded log for the whole frame, you need to multiply the number of cubes received by the price of a log for one cubic meter. The cost of one meter of a cubic rounded log can be found out here .
To perform calculations for other log diameters, we bring to your attention a number of pre-calculated tables, using which you will surely find answers to your questions.
The article was prepared by the company ASK Aegis which performs construction of houses from logs and renders wide range of construction services in the suburban housing market.
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Methodology for calculating the mass and volume of felling residues
One of the tasks in the development of the draft technological regulation of the Construction and Demolition Waste Management Process is to calculate the mass and volume of felling residues formed during the cutting down of green spaces (demolition of trees) in the construction or demolition zone.
There is no official methodology for calculating the mass and volume of felling residues for these purposes in the Russian Federation. The initial data for such calculations are information about the trees cut down (species, height and thickness at a height of 1.3 m) and shrubs (young stands), given in the inventory list from the design documentation for the construction (demolition) object.
This article presents a methodology for calculating the mass and volume of felling residues, developed in our company. As a basis for its development, the tabular data of the All-Union standards for forest taxation, approved by the Order of the State Committee for Forestry of the USSR dated February 28, 1989, No. 38, were used.
1) The data in Table 17 "Trunk volumes (in bark) in young stands in height and diameter at a height of 1.3 m" - to determine the volume of trunks of young growth and shrubs.
Round log cubicle
As a result of processing the above data to determine the average ratio between the diameter (D), height (h) and volume (V) of one trunk, the calculated shape factor (Kp from Table 1) was determined, which, with an accuracy of +/- 10%, allows to determine the volume of the trunk by formula Vst = Kn * h * pD2 / 4.
2) The data of tables 18 and 19 "Volumes of trunks (in the bark) of tree species in height and diameter at a height of 1.3 m with an average shape factor" "- to determine the volume of trunks of various tree species. As a result of processing the above data to determine the average ratio between the diameter (D), height (h) and volume (Vst) of one trunk, the calculated coefficients were determined for some of the tree species listed in the table, which, with an accuracy of +/- 10%, makes it possible to determine the volume of the trunk according to the formula Vst = Kn * h * pD2 / 4. Calculated form factors are shown in table 1
3) Table data 185 “Mass of 1 cubic meter. m and the volume of 1 ton of wood of different species "- to determine the mass of wood, we used the values of the mass of one cubic meter of the corresponding wood species from the column" freshly cut ", or from the column" dry "- for dead wood.
4) The data of table 206 "Volume of bark, branches, stumps and roots" to determine the volume of branches and branches, as well as stumps and roots as a percentage of the volume of trunks. For the calculation, the average values from the interval given in the tables were used. The volume of twigs and branches - 7% of the volume of the trunks, the volume of stumps and roots - 23% of the volume of the trunks.
5) The data in table 187 "Coefficients of full wood content of brushwood and chmyz" - to determine the fold volume of branches and branches from full wood volume using a conversion factor equal to 10.
FKKO-2014 contains codes for the following waste:
1 52 110 01 21 5 Waste branches, branches, tops from logging
1 52 110 02 21 5 Waste from the removal of stumps
1 54 110 01 21 5 Waste of low-value wood (brushwood, dead wood, fragments of trunks).
Therefore, the calculation of the mass and volume of felling residues must be calculated by type of waste:
- the trunks of trees, young growth and shrubs cut down according to the inventory list can be attributed to waste of low-value wood (brushwood, dead wood, fragments of trunks);
- twigs and branches - to waste branches, branches, tops from logging;
- stumps and roots - to waste of uprooting stumps.
For the technological regulations of the Construction and Demolition Waste Management Process, 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 also necessary to estimate the volume of felling 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 made in the following order:
1) Filling in the initial data according to the inventory;
column 2 - line number of the counting sheet;
column 3 - wood species;
column 4 - the number of trees;
column 5 - the minimum diameter of the trunk from the interval indicated in the listing;
column 6 - the only value of the trunk diameter indicated in the listing;
column 7 - the maximum diameter of the trunk from the interval indicated in the listing;
column 8 - the minimum height of the trunk from the interval indicated in the counting sheet;
column 9 - the only value of the trunk height indicated in the counting sheet;
column 10 - the maximum height of the trunk from the interval indicated in the counting sheet;
column 11 - additional number of trunks - if in the column "characteristic 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 in the presence of 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 barrel<объем ствола (графа 12)>produced according to Vst = Kn * h * pD2 / 4, where Kn is the corresponding form factor from Table 1, D is the average diameter of the trunk, h is the average height of the trunk. Calculation of the volume of one barrel:<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 a dense measure of the volume of trunks 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 assumed to be 5 .;
5) Calculation of the storage measure (when storing or transporting, it is necessary to take into account the average volume of space occupied by the trunks of trees or bushes:<складочная мера объема стволов (графа 14)>= <плотная мера объема стволов (графа 13)>* 4 / p;
6) The calculation of the volume of branches 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 a fold measure - in accordance with 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) The 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 taken in a 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 the fold (this indicator most objectively allows you to assess the need for the capacity of the bodies (containers) of vehicles for the removal of felling 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 that are not 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 branches 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) The total weight of the removed waste (felling 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 makes it possible to calculate the volume (both full and stock) and the mass of felling residues with differentiation by the type of waste based on the initial data of the inventory, as well as to estimate the required volume of storage bins or vehicle bodies and the number of car trips for their export.
K. Nikonenko
It makes no sense to perform the same calculations several times if the initial 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 counting in which city. Only the formula V = πr²l gives the correct answer.
How to calculate the volume of a forest
Therefore, the volume of one OTSB will always be V = 3.14 × (0.1) ² × 6 = 0.1884 m³. In practice, in order to exclude the moment of carrying out standard calculations, cubatures are used. Such useful and informative tables are created for various types of lumber. They help to save time and find out the cubic capacity of round timber, boards, OCB, timber.
- Roundwood cubicle
- How to use the table?
- Cubic capacity of products of different sizes
What is a cubicle box?
The name of this building handbook is due to the fact that volume as a physical quantity is measured in cubic meters (or cubic meters). For a simpler explanation, they say "cubature", respectively, the table was called "cubature". This is an ordered matrix, which 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 a concrete example - a roundwood cubicle. It was approved in 1975 and is called GOST 2708-75, the main parameters are diameter (in cm) and length (in meters). It is very simple to use the table: 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 cubicle for round timber exists according to a different standard - ISO 4480-83. Reference books are very detailed with a step of 0.1 m, as well as more general, where the length is taken in 0.5 m increments.
Little secrets
The very use of the cubature is not difficult, but the main nuance is the correct data. Round wood is not a cylinder, but a truncated cone, in which the lower and upper cuts differ. One of them may be 26 cm, and the other - 18. The table assumes an unambiguous answer for a specific section.
Various sources suggest doing in two ways: to 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 according to the accompanying instructions. For a cubic meter GOST 2708-75, the diameter of the upper cut of the log is taken. Why is the raw data point 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 cubes. If in the GOST 2708-75 table, complex formulas for truncated cones were used, calculations were carried out, and the results were rounded up to thousandths, then modern companies that make up their own cubic meters take liberties. For example, instead of 0.156 m³ there is already a number of 0.16 m³. Often, openly erroneous cubes are posted on Internet sites, in which the volume of a log 5 meters long with a diameter of 18 cm is indicated not 0.156 m³, but 0.165 m³. If a company uses such directories, selling round timber to consumers, then it makes a profit, actually deceiving customers.
After all, the difference per item is significant: 0.165-0.156 = 0.009 or almost 0.01 m³.
The main problem of round timber is a different section. Sellers offer to resolve issues with calculations 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 the calculation of the volume of each log and the subsequent addition of the numbers guarantees that the buyer pays for the timber 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, and then multiply by the length (in meters).
2. Warehousing method.
It is assumed that the stored round timber occupies a part of the space in the form of 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 the acceptance as an indisputable fact that wood occupies 80% of the total space. After all, it may well happen that the bars are not neatly folded, 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. Cubature is easily found by dividing the first number by the second. But the result will be very imprecise, since a tree of the same species has a different density. The indicator depends on the degree of maturity and moisture.
4. Averaged method.
If the trunks of the harvested trees are almost the same in appearance, then choose any 3 of them. The diameters are measured, and then the average is found. Further, according to the cubic meter, the parameter for 1 product is determined and multiplied by the required amount. Let the results show: 25, 27, 26 cm, then the average is considered to be Ø26 cm, since (25 + 26 + 27) / 3 = 26 cm.
Taking into account the disadvantages of the considered methods, the only correct way to calculate the cubic capacity is to find the volume of each log using a cubic meter GOST 2708-75 or ISO 4480-83 and summing up the data obtained.
Calculation of the cubic capacity of lumber - count correctly
In the process of building structures made of wood, various lumber is purchased.
When buying or selling it, it becomes necessary to measure it. All the complexity of measuring lumber due to its inconsistent and non-standard size and shape, weight and quality. Due to the factors mentioned above, it is also impossible to sell such a product by piece. Make it right calculation of the cubic capacity of lumber It is very difficult for a non-specialist, and even the regulatory authorities are sometimes not able to check whether the calculation is correct.
Some sawn timber from the manufacturer is supplied in packages with an indication of the exact volume and value. But this practice is quite rare. In addition, consumers may have doubts about the correctness of calculating the cubic capacity of lumber, as well as about the indicated price. An ordinary buyer does not always know that in addition to cubic capacity, the cost of lumber depends on the degree of their processing, that is, non-edged or edged board, wood species and grade. In addition, the cost of boards up to 1.7 m long is lower than the cost of longer boards. The quality of the lumber produced is regulated by a huge number of rules and regulations, technical conditions and other regulatory documents, which individual developers do not even suspect, at the same time sellers of lumber are in no hurry to familiarize their buyers with the rules for the sale of lumber. In order to have at least a general idea of how the cubic capacity of lumber is calculated, it will not be superfluous to familiarize yourself with the rules for measuring some of their most common types.
According to the current regulations, the slab must be sorted, depending on the length, into two groups - up to two meters and over two meters. The croaker is stacked, alternating between thick and thin ends, as well as a crooked surface. The stacks should be of the same height along their entire length, right angles, they must be stacked as tightly as possible. Then, multiplying the width, length and height of the package, you get the folded cubic capacity.
Calculation of the volume of round timber
| Thickness in the upper cut, see |
Volume m³, length, m. | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| 1 | 1,5 | 2 | 2,5 | 3 | 3,5 | 4 | 4,5 | 5 | 5,5 | 6 | |
| 14 | 0,016 | 0,025 | 0,035 | 0,043 | 0,052 | 0,061 | 0,073 | 0,084 | 0,097 | 0,110 | 0,123 |
| 16 | 0,021 | 0,035 | 0,044 | 0,056 | 0,069 | 0,082 | 0,095 | 0,110 | 0,124 | 0,140 | 0,155 |
| 18 | 0,027 | 0,041 | 0,056 | 0,071 | 0,086 | 0,103 | 0,120 | 0,138 | 0,156 | 0,175 | 0,194 |
| 20 | 0,033 | 0,051 | 0,069 | 0,087 | 0,107 | 0,126 | 0,147 | 0,170 | 0,190 | 0,210 | 0,23 |
| 22 | 0,040 | 0,062 | 0,084 | 0,107 | 0,130 | 0,154 | 0,178 | 0,200 | 0,230 | 0,250 | 0,28 |
| 24 | 0,048 | 0,075 | 0,103 | 0,130 | 0,157 | 0,184 | 0,210 | 0,240 | 0,270 | 0,300 | 0,33 |
| 26 | 0,057 | 0,089 | 0,123 | 0,154 | 0,185 | 0,210 | 0,250 | 0,280 | 0,320 | 0,350 | 0,39 |
| 28 | 0,067 | 0,104 | 0,144 | 0,180 | 0,220 | 0,250 | 0,290 | 0,330 | 0,370 | 0,410 | 0,45 |
| 30 | 0,077 | 0,119 | 0,165 | 0,200 | 0,25 | 0,29 | 0,33 | 0,38 | 0,42 | 0,47 | 0,52 |
| 32 | 0,087 | 0,135 | 0,190 | 0,230 | 0,28 | 0,33 | 0,38 | 0,43 | 0,48 | 0,53 | 0,59 |
| 34 | 0,100 | 0,150 | 0,210 | 0,260 | 0,32 | 0,37 | 0,43 | 0,49 | 0,54 | 0,60 | 0,66 |
| 36 | 0,110 | 0,170 | 0,230 | 0,290 | 0,36 | 0,42 | 0,48 | 0,54 | 0,60 | 0,67 | 0,74 |
| 38 | 0,120 | 0,190 | 0,260 | 0,320 | 0,39 | 0,46 | 0,53 | 0,60 | 0,67 | 0,74 | 0,82 |
| 40 | 0,14 | 0,21 | 0,28 | 0,36 | 0,43 | 0,50 | 0,58 | 0,66 | 0,74 | 0,82 | 0,90 |
| 42 | 0,15 | 0,23 | 0,31 | 0,39 | 0,47 | 0,56 | 0,64 | 0,73 | 0,81 | 0,90 | 1,0 |
| 44 | 0,16 | 0,25 | 0,34 | 0,43 | 0,52 | 0,61 | 0,70 | 0,80 | 0,89 | 0,99 | 1,09 |
| 46 | 0,18 | 0,27 | 0,37 | 0,47 | 0,57 | 0,67 | 0,77 | 0,87 | 0,94 | 1,08 | 1,19 |
| 48 | 0,19 | 0,30 | 0,41 | 0,51 | 0,62 | 0,73 | 0,84 | 0,95 | 1,06 | 1,18 | 1,30 |
Volume of 10 m of coniferous wood beams, m³
| Width, mm | Thickness, mm | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| 50 | 60 | 75 | 100 | 130 | 150 | 180 | 200 | 220 | 250 | |
| 130 | 0,065 | 0,078 | 0,0975 | 0,13 | ||||||
| 150 | 0,075 | 0,09 | 0,0113 | 0,15 | 0,195 | 0,225 | ||||
| 180 | 0,09 | 0,108 | 0,0135 | 0,18 | 0,234 | 0,27 | 0,324 | |||
| 200 | 0,1 | 0,12 | 0,015 | 0,2 | 0,26 | 0,3 | 0,4 | |||
| 220 | 0,11 | 0,132 | 0,0165 | 0,22 | 0,395 | 0,434 | ||||
| 250 | 0,125 | 0,15 | 0,188 | 0,25 | 0,5 | 0,625 |
In the woodworking industry, there are concepts of folding and dense cubic meter. In the price list for sawn timber, they are indicated for the volume in a dense mass, therefore, the cubic meters must be converted to a dense mass. For this, special conversion factors are used. For example, for a slab with a length of up to two meters, a coefficient of 0.48 is used, and for a slab with a length of more than two meters - 0.43.
There are two ways to determine the volume of sawn softwood and hardwood. Either by measuring each unit of material, or using a special standard, or a cubic meter established by GOST and designed to determine the volume of deciduous and coniferous edged sawn timber. 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 non-edged sawn timber, slightly different rules apply.
How to accurately calculate the cubic capacity of a log?
The specificity of their measurement lies in the fact that the width of one-sided edged and non-edged 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. Dense cubic meters of logs are calculated using the corresponding GOST, which indicates the volume of round timber. These volumes are measured along the length of the log and the thickness of the top end.
The table we offer shows calculation of lumber cubic capacity: edged and unedged boards, floor boards, bars, beams, lining and slats. Using the table, you can calculate the amount of lumber in 1 m3.
| The size | The volume of one board (bar) | Quantity in 1m3 |
|---|---|---|
| Beams | ||
| 100x100x6 | 0.06 cube | 16.67 pieces |
| 100x150x6 | 0.09 cube | 11.11 pieces |
| 150x150x6 | 0.135 cube | 7.41 pieces |
| 100x200x6 | 0.12 cube | 8.33 pieces |
| 150x200x6 | 0.18 cube | 5.56 pieces |
| 200x200x6 | 0.24 cube | 4.17 pieces |
| 100x100x7 | 0.07 cube | 14, 28 pieces |
| 100x150x7 | 0.105 cube | 9.52 pieces |
| 150x150x7 | 0.1575 cube | 6.35 pieces |
| 100x200x7 | 0.14 cube | 7.14 pieces |
| 150x200x7 | 0.21 cube | 4.76 pieces |
| 200x200x7 | 0.28 cube | 3.57 pieces |
| Edged board | ||
| 22x100x6 | 0.0132 Cubes | 45.46 sq.m. |
| 22x150x6 | 0.0198 cube | 45.46 sq.m. |
| 22x200x6 | 0.0264 Cubes | 45.46 sq.m. |
| 25x100x6 | 0.015 cube | 40 sq. |
| 25x150x6 | 0.0225 cube | 40 sq. |
| 25x200x6 | 0.03 cube | 40 sq. |
| 40x100x6 | 0.024 cube | 25 sq. |
| 40x150x6 | 0.036 cube | 25 sq. |
| 40x200x6 | 0.048 cube | 25 sq. |
| 50x100x6 | 0.03 cube | 20 sq. |
| 50x150x6 | 0.045 cube | 20 sq. |
| 50x200x6 | 0.06 cube | 20 sq. |
| 32x100x6 | 0.0192 Cubes | 31.25 sq. |
| 32x150x6 | 0.0288 cube | 31.25 sq. |
| 32x200x6 | 0.0384 Cubes | 31.25 sq. |
| 25x100x2 | 0.005 cube | 40 sq. |
| 25x100x7 | 0.0175 cube | 40 sq. |
| 25x150x7 | 0.02625 cube | 40 sq. |
| 25x200x7 | 0.035 cube | 40 sq. |
| Unedged board | ||
| 50x6 | 0.071 1 cube | |
| 40x6 | 0.05 1 cube | |
| 25x6 | 0.0294 1 cube | |
| Rail | ||
| 22x50x3 | 0.0033 cube | 909 rm |
| 25x50x3 | 0.00375 cube | 800 rpm |
| 22x50x2 | 0.0022 cube | 909 rm |
| 25x50x2 | 0.0025 cube | 800 rpm |
| Bar | ||
| 40x40x3 | 0.0048 cube | 624.99 rpm |
| 50x50x3 | 0.006 cube | 500.01 rpm |
| 40x80x3 | 0.0096 cube | 312.51 m.p. |
| 50x50x3 | 0.0075 cube | 399.99 rpm |
| Floor board | ||
| 36x106x6 | 0.0229 cube | 27.77 sq.m. |
| 36x136x6 | 0.0294 Cubes | 27.77 sq.m. |
| 45x136x6 | 0.0375 cube | 21.74 sq.m. |
| Lining | ||
| 16x88x6 | 0.0084 cube | 62.5 sq.m. |
| 16x88x3 | 0.0042 cube | 62.5 sq.m. |
| 12.5x90x3 | 0.0034 cube | 80 sq. |
The purpose of this article is to explain to you how to correctly calculate the area of \ u200b \ u200bthe walls of log houses, baths and other buildings, as well as buildings from glued and profiled beams. Many will say - What is there to explain and so everything is clear - you just need to know the basics of geometry.
Roundwood cubes - how to calculate the volume?
Quite right - you can't do without geometry, but this dimension 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 cabins is calculated:
- will help to more accurately calculate the cost and amount of required material *
- calculate independently the cost of painting and polishing log cabins
To calculate the area of \ u200b \ u200bthe walls, we all know that we must know two quantities - the height and the length, and for a complete calculation, the area also of the ends
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 the total area of the ends.
The main feature of 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 # 2
We calculate the area.
To measure the height of one log, you just need to take a tape measure and set it aside 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, an average value is taken). And at the timber you need to measure the width of the edges and add it to the value A(arrows shown in photo # 2). We will get the real height of one log or bar, and knowing the number of crowns, we get the real height of the wall (number of crowns * height of one crown). I think you shouldn't remind me of the formula for the area of a rectangle. It's that simple.
Photo # 4.
And so, adding up all the data - the area of the walls, "triangles", ends and from the resulting amount subtract the area of the window and door openings - we will get the full area of the building and already based on these 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 handing them over to the company manager by phone or arriving at the office) **.
Finally, I will give a little advice, if by measuring the structure of a simple form everything is simple and does not make much work and does not require much time, but what about complex forms, such as on photo # 4.
photo # 4
I'll tell you straight - measure yourself or be present at the measurements when your employees do it, by this you will avoid deception from unscrupulous construction crews or contact trusted companies.
* the cost and volume of the required material (coating) is influenced by the condition of the wood (sanded, not sanded) and the coating method (brush, roller, spray)
** for your convenience, on our website, the cost of materials is calculated for 1m2
Still have questions? Call
(A. Sokolov, Terem Grad)
One of the ways to make reasonable savings is to purchase building materials in the required quantity, no more and no less. A private developer knows very well how many and what samples he needs to purchase to perform a specific job. But the difficulty is that the boards are not sold by the piece, with rare exceptions - only in batches (packs). And no one buys several pieces for construction. How to determine how much m 3 of wood to buy?
How to choose lumber?
1. Deal with the types of necessary blanks, based on the specifics of their further use. This product is classified as edged board, obapol and unedged. If wood is needed for both, then the purchase volume will have to be calculated for each type of product separately.
2. Determine the required linear parameters of products and translate them into one dimension. Since the cubic capacity is m 3, in order to make it easier to count later, the length, width and thickness should be recorded in meters.
During the construction process, boards of different lengths are required. If they are very different in this parameter, then it is worth calculating the cubic capacity for each group separately - this way you can reduce waste during cutting. It is advisable, before counting, to find out how long the products are sold on the building materials market. The fact is that for them, each manufacturer may have their own standard sizes. These values should be used to group products, and then calculate how many and what boards are required. If you draw up a table for yourself and think over everything well, then it will come out to save a lot.
Features of calculating the volume of lumber
There are typical tables designed to determine the volume of various blanks (logs, boards, beams). You can also calculate with the help of calculators that are available on thematic sites. But in practice, in "field" conditions, you have to work in a "manual" mode. That is, to count the cubic capacity of the board, using only a tape measure, since the piles on the market are not stacked exactly at 1 m 3.
1. Edged board.
Example (for those who forgot school).
- Let's calculate the approximate (since errors are inevitable when measuring) the cubic capacity of the "magpie" 6 m long and 200 mm wide. Making a translation, it turns out: width - 0.2; thickness - 0.04 (m).
- Therefore, the cubic capacity of 1 edged board with the given parameters is 6 x 0.2 x 0.04 = 0.048 m 3. The technique is simple, the main thing is not to forget to translate all dimensions in "m".
- If you need to calculate how many boards are in a "cube", then such an arithmetic operation is performed - 1 m 3 is divided by cubic capacity.
- In our example - 1 / 0.048 = 20.83. Round up to a whole number - 21 pieces.
2. Unedged products.
The side faces are not machined. As a rule, products are packed in packs with re-grading. This means that the wood can be of different species, and the standard sizes (especially the width of the workpiece) differ. In this case, it is rather difficult to calculate the volume of the stack. Should:
- Examine the pack carefully. The task is to choose the 2 most even boards. Moreover, one is the narrowest, the other is the widest.
- Remove all dimensions from each and calculate the average values for length, width and thickness.
Example. The width of one workpiece is 15 cm, the other is 35. Fold and divide in half - (15 +35) / 2 = 25 cm. For further calculations, translate into meters - 0.25. Other average linear parameters are determined by the same method.
What is the peculiarity of calculations for unedged sawn timber? They have uneven side edges. Consequently, due to curvatures, the fit of the samples to each other is not so tight. The result is gaps and voids. Therefore, a correction factor is taken, which largely depends on the moisture content and type of wood. Its minimum value is 0.62, and the maximum is 0.7.
In practice, the quality of materials is determined "by eye", therefore the average correction is taken - 0.66. To get the final result, you need to multiply the resulting cubic capacity by the specified coefficient.
If you work with a large stack, then the probability of an error in the calculations increases dramatically. In order not to overpay, it is advisable to store the boards in packs of pieces of 10. For each of them, measurements are taken with subsequent calculations of the cubic capacity.
According to the same technique, calculations are made for the obapol (slab). The only difference is in the ratio. Its value lies in the range of 0.48 - 0.74.