- Algorithm for calculating cubic capacity
- How to calculate the cubic capacity of round timber for building a house
- Calculation of cubic capacity using the formula
People who want to fulfill their dreams of building a house, a bathhouse or other buildings made of wood are certainly faced with the inevitability of acquiring materials such as logs, timber and boards in quantities necessary and sufficient for construction.
Table for calculating the cubic capacity of logs.
All this is taken into account and realized in cubic meters (m3). The greatest difficulties are caused by calculations of the exact required volume of these materials necessary for the construction of the planned house. First of all, it is not clear how to calculate the cubic capacity of the required round timber.
Depending on the climate of the region in which it is planned to construct a building from timber, the thickness of the round timber used is selected. The higher the winter temperature, the smaller the diameter of the scaffolding used for the construction of external walls can be. For example, in a region where winter temperatures do not drop below -20 °C, round timber of small diameters, up to 180 mm, can be used. On the contrary, at winter temperatures below -40°C it is worth using thicker wood, which better retains heat in the house. At different thickness the material used and its cubic capacity will also be different.
Algorithm for calculating cubic capacity
Scheme for calculating forest cubic capacity.
The algorithm for obtaining the final data is quite simple: based on a given building drawing, they calculate the total amount of round timber that will be used for the construction of the planned house or other structure. Moreover, when determining the specified quantity, the desired (necessary) thickness of these timber products (their diameter or radius) must be taken into account. After that, the average volume of one log is determined and, knowing their total required quantity, the final volume required for the construction of round timber is obtained. The approximate volume of one piece of wood is calculated using the formula for determining the volume of a cylinder, based on its diameter (radius) and height (length).
Example 1. Scheme for calculating the cubic capacity of a log.
However, to apply such an algorithm, it is necessary that the round timber being counted meets the following criteria:
- their shape should correspond to the shape of the cylinder;
- they must be the same diameter and the same length.
It would seem quite easy. But the fact is that sometimes you have to calculate the cubic capacity of logs of different formats used. Methods for determining the cubic capacity of rounded timber (pre-processed, in which the top and butt of the same diameter, that is, actually having the shape of a cylinder) and unprocessed, with different sizes the top and butt (to some extent corresponding to the shape of a truncated cone) are somewhat different.
Return to contents
How to calculate the cubic capacity of round timber for building a house
GOST 2708-75 helps solve such problems, containing tables that can be used to determine the volume of round timber. Determination is made by the following parameters of these materials: by the diameter of the apex (the thinnest end) and length. It is recommended to use the arithmetic mean of two measurements of the top diameter, taken perpendicular to each other, as the working diameter for determining the cubic capacity table, if the upper end part differs greatly from the standard circle shape.
Return to contents
Calculation of cubic capacity using the formula
Notation diagram for calculating cubic capacity using the formula.
If you don’t have such tables at hand, use the following volume calculation formula -
- π = 3.1416;
- r – radius of the vertex (in meters);
- L – length (in meters).
However, this method, which makes it possible to calculate the cubic capacity of a log, is used for rounded timber or those in which the narrowing from the butt to the top is no more than 0.8 cm per 100 cm of length.
For such materials, an averaged inverse method is also used to determine the number of identical timbers in one cubic meter of round timber. The method is based on calculating the cubic capacity of a certain conventional round timber with the parameters: r – 0.1 m and L – 6 m. The volume of this round timber is quantitatively equal to 0.1884 cubic meters. m, obtained as a result of the calculation, makes it possible to calculate that one cubic meter of such timber will contain 1/0.1884 = 5.3 pieces.
Example 2. Scheme for calculating the cubic capacity of a log.
- π = 3.1416;
- D – butt diameter (in meters);
- d – diameter of the top (in meters);
- L – length (in meters);
- a is a coefficient that takes into account the “runaway” of round timber depending on its size.
Table of coefficient “a” values:
Practice shows that it is impossible to correctly calculate the cubic capacity of unsorted timber without taking into account the correction factor “a”. Errors in quantity that occur when ordering round timber for building a house are usually due to the fact that this coefficient is not taken into account in the calculations.
Currently, electronic wood volume calculator programs can also be used for such calculations. different types, from PC versions to versions for cell phones and smartphones. Volume calculations in the calculator can be carried out in accordance with GOST 2708-75 or ISO 4480-83.
There is also a method for approximate estimation of the cubic capacity of round timber, which is used for unsorted timber stacked in a stack. Its essence is that the dimensions of the stack (length, width, height) determine its cubic capacity. Then, taking into account the space between the scaffolds and the unevenness in their length, the final result is adjusted. This method can be used when quickly assessing the volume of a batch of timber offered for sale or construction supplies prepared for use.
As a result, we can conclude that calculating the cubic capacity of a log is much easier for graded and rounded timber, which, moreover, especially the latter, are very attractive when building a beautiful log house.
Correctly calculated quantity necessary materials- this is the basis for an accurately drawn up estimate for construction and, accordingly, a decision in full on the necessary financing of the planned work.
http://masterbrusa.ru
The cubic capacity of a log is the volume wood material, measured in cubic meters. This value is used in the construction of wooden log houses to calculate the amount of round timber. Determining cubic capacity is important when selling firewood, where payment is required for each cubic meter tree. How to calculate the volume of round cylindrical lumber correctly?
It is necessary to know the cubic capacity of a tree when purchasing this building material, since payment is made for each cubic meter.
There are several ways to roughly estimate the cubic capacity of roundwood or firewood. All established methods use data from measuring geometric dimensions and mathematical calculations. A tape measure is traditionally used to measure construction values.
Calculation of cubic capacity of occupied space
The simplest method is to define a cubic rectangular space in which the timber is folded. Such a place could be the back of a dump truck or a barn. You can also calculate the geometric dimensions of a woodpile if it is folded into a neat rectangle.
Since the spatial cubic capacity is not completely filled with wood, the determined value is reduced using the voids coefficient. In construction calculations, the void ratio is considered to be 0.8. That is, 20% of the space is occupied by air voids, and 80% by wood.
Cubic size is defined as follows:
- The length, width and height of the rectangular space are measured.
- The resulting values are multiplied with each other to obtain the volume value.
- The resulting value is multiplied by a factor of 0.8, which takes into account the approximate number of voids between round logs.
- The resulting value is taken as the required volume of the log.
This method is used to calculate the cubic capacity of round timber, boards, and firewood of different sizes.
Return to contents
Calculation of the volume of individual logs
Figure 1. Measuring two perpendicular diameters in a beam cross-section
If round wood characterized by the same long logs and similar diameter, then you can calculate the volume of selectively 3 logs and reduce them to the average calculated value and multiply it by the quantity log material. In this case, the calculations are performed as follows:
- Choose any 3 timbers.
- Measure their diameter and length. For ease of calculation, measurements are made in meters.
- Calculate the cubic space occupied by each of the round timbers using the formula:
where Pi is a number equal to 3.14,
R – radius equal to half the measured diameter,
L – beam length.
- The resulting values of 3 cubic meters of roundwood will be close to each other. They must be added up and the sum divided by 3. Thus, we obtain the value of the average volume of one log.
- Next we multiply the resulting average value on the number of workpieces in the machine or storage.
Since logs of similar diameters and standardized lengths are used for construction, this method is widely used to estimate the cubic capacity of scaffolding.
If the shape of the beam is slightly pressed down, its cross-section will not be round, but slightly oval. How then to determine the diameter value? To do this, measure the size of 2 perpendicular diameters in the section of the beam: the largest and the smallest. Next, the measured values are summed and divided by 2. The resulting value will be the average diameter used in the calculations (Fig. 1).
When implementing construction work for the construction of a residential building, a specialist must perform big number various tasks, some of which are: drawing up and calculating the estimated cost to final finishing premises of a residential building. IN mandatory, calculate the required amount of various building materials, which is quite difficult to do. Therefore, such knowledge - how many boards are in a cube - has a very important for a specialist who is engaged in the construction of a residential building and wants to complete the work as efficiently and quickly as possible.
Buying club: existing types of boards
To calculate exactly how many board pieces are in a cube, you will need to know not only what exactly a board cube means, but it is worth understanding important point that exist different kinds boards and what is possible to purchase on modern market for performing various construction works. It should be noted that the cube of almost all materials, regardless of the type of material, is calculated in the same way, that is, according to one specific method. The types of boards have no influence on the calculation of the cubic capacity of this building material.
Non-grooved types of lumber are: timber, various edged boards, as well as unedged boards (they are an exception when calculating cubic capacity, because this process occurs a little differently). Tongue-and-groove types (which have special grooves for making joints) include: modern lining, blockhouse, flooring material, as well as imitation natural timber. When you choose a tongue-and-groove type of building material for purchase, then you will need to pay attention to the fact that when making calculations, only the working width of the board without a tenon is used. If we talk about a blockhouse (imitation log), then when calculating the cubic capacity, only the thickness at its highest point is taken.
How many boards are in 1 cube: performing the calculation
Any person, even from his school days, understands how cubic capacity is calculated. For this procedure, it is necessary to calculate quantities such as: length, width and height. A similar principle is used to calculate the cubic capacity of 1 board. When performing such calculations, it is recommended to convert all available values into meters. The cubic capacity of 1 board, which has a cross-section of 150x20 mm. and a length of 6 m, is calculated as follows: 0.15 multiplied by 0.02 and 6, so that the cubic capacity of this board will be 0.018 cubic meters.
Let's apply the volume formula V= L*h*b (where L is length, h is height, b is width).
L= 6.0; h= 0.02; b= 0.15.
Thus, V= 6.0*0.02*0.15 = 0.018 m3.
To determine how many boards are in one cube: divide 1 m3 by cubic capacity (the volume of one board).
1 m 3 / V = N pcs.
1 m 3 / 0.018 m 3 = 55.55 pcs.
Thus, the number of boards in one cube is 55.5 pieces.
Find out the cost certain type boards, when the values of its volume are known quite easily: 0.018 is multiplied by the price of 1 cubic meter. When 1 cube of a certain type of board costs, for example, 5,500 rubles, then the cost will be 99 rubles. At this point in the calculation, there is some trick of sellers and managers in construction stores, because the cubic capacity of the material is rounded to some integer values.
Such rounding can lead to such a moment that the price of 1 board (when 1 cube costs 5500) will be completely different values. In addition to all this, it should be noted that various boards for construction, which have a nominal length of 6 meters, the actual length is 6.1 - 6.2 m, which is not taken into account when selling this building material. This also applies to the purchase of a significant number of boards. This can be seen quite clearly if we use a 150x20 mm board as an example. The number of boards in a cube is a value of 55.5 pcs. But, in a cube they count 55 pieces, which when performing the calculation will have a value of 0.99 cubic meters. In fact, it follows from this that the overpayment for 1 cubic meter of this popular building material can amount to 1% of the real price. For example, 5500 instead of 4995 rubles.
To calculate the cubic capacity for a continuous type of board, slightly different methods are used. When we are talking about buying 1 board, then measuring its thickness, as well as the total length, is carried out in the same way as when choosing edged building material. In this case, the average width is taken for calculations - between a large value and a small one.
For example, when the width of the board at one end is 25 cm, and at the other 20, then the average value will be approximately 22 centimeters. When it is necessary to calculate the volume of a significant number of similar boards for construction, then you will need to lay them out so that the wide one does not differ from the narrow one, more than 10 cm. The main length of this material in the laid out stack should be approximately the same. After this, using a regular tape measure, an accurate measurement is made of the height of the entire existing stack of boards, and the width is measured (approximately in the very middle). The result obtained will then need to be multiplied by a special coefficient, amounting to a value from 0.07 to 0.09, directly dependent on the existing air gap.
How many boards are in 1 cube: special tables
To calculate the exact number of boards of a certain width and length in 1 cubic meter, various tables are used. Below are several such specialized tables, which indicate the cubic capacity of the common and in demand types of this material today. It is possible to calculate the volume of various boards of different sizes, for example, material for erecting a fence on your site, using the existing formula presented above.
Table of the amount of edged boards in 1 cubic meter
| Board size | Volume of 1st board (m 3) | Number of boards in 1m 3 (pcs.) | Number of square meters in 1m2 |
|---|---|---|---|
| Twenty | |||
| Board 20x100x6000 | 0.012 m 3 | 83 pcs. | 50 m2 |
| Board 20x120x6000 | 0.0144 m 3 | 69 pcs. | 50 m2 |
| Board 20x150x6000 | 0.018 m 3 | 55 pcs. | 50 m2 |
| Board 20x180x6000 | 0.0216 m 3 | 46 pcs. | 50 m2 |
| Board 20x200x6000 | 0.024 m 3 | 41 pcs. | 50 m2 |
| Board 20x250x6000 | 0.03 m 3 | 33 pcs. | 50 m2 |
| Twenty-five | |||
| Board 25x100x6000 | 0.015 m 3 | 67 pcs. | 40 m2 |
| Board 25x120x6000 | 0.018 m 3 | 55 pcs. | 40 m2 |
| Board 25x150x6000 | 0.0225 m 3 | 44 pcs. | 40 m2 |
| Board 25x180x6000 | 0.027 m 3 | 37 pcs. | 40 m2 |
| Board 25x200x6000 | 0.03 m 3 | 33 pcs. | 40 m2 |
| Board 25x250x6000 | 0.0375 m 3 | 26 pcs. | 40 m2 |
| Thirty | |||
| Board 30x100x6000 | 0.018 m 3 | 55 pcs. | 33 m2 |
| Board 30x120x6000 | 0.0216 m 3 | 46 pcs. | 33 m2 |
| Board 30x150x6000 | 0.027 m 3 | 37 pcs. | 33 m2 |
| Board 30x180x6000 | 0.0324 m 3 | 30 pcs. | 33 m2 |
| Board 30x200x6000 | 0.036 m 3 | 27 pcs. | 33 m2 |
| Board 30x250x6000 | 0.045 m 3 | 22 pcs. | 33 m2 |
| Thirty-two | |||
| Board 32x100x6000 | 0.0192 m 3 | 52 pcs. | 31 m2 |
| Board 32x120x6000 | 0.023 m 3 | 43 pcs. | 31 m2 |
| Board 32x150x6000 | 0.0288 m3 | 34 pcs. | 31 m2 |
| Board 32x180x6000 | 0.0346 m 3 | 28 pcs. | 31 m2 |
| Board 32x200x6000 | 0.0384 m 3 | 26 pcs. | 31 m2 |
| Board 32x250x6000 | 0.048 m 3 | 20 pcs. | 31 m2 |
| Sorokovka | |||
| Board 40x100x6000 | 0.024 m 3 | 41 pcs. | 25 m2 |
| Board 40x120x6000 | 0.0288 m3 | 34 pcs. | 25 m2 |
| Board 40x150x6000 | 0.036 m 3 | 27 pcs. | 25 m2 |
| Board 40x180x6000 | 0.0432 m 3 | 23 pcs. | 25 m2 |
| Board 40x200x6000 | 0.048 m 3 | 20 pcs. | 25 m2 |
| Board 40x250x6000 | 0.06 m 3 | 16 pcs. | 25 m2 |
| Fifty | |||
| Board 50x100x6000 | 0.03 m 3 | 33 pcs. | 20 m2 |
| Board 50x120x6000 | 0.036 m 3 | 27 pcs. | 20 m2 |
| Board 50x150x6000 | 0.045 m 3 | 22 pcs. | 20 m2 |
| Board 50x180x6000 | 0.054 m 3 | 18 pcs. | 20 m2 |
| Board 50x200x6000 | 0.06 m 3 | 16 pcs. | 20 m2 |
| Board 50x250x6000 | 0.075 m 3 | 13 pcs. | 20 m2 |
Table of the amount of timber in 1 cubic meter
| Beam size | Volume of 1st piece (m³) | Quantity of timber in 1m³ (pcs.) |
|---|---|---|
| 100×100×6000 | 0.06 m 3 | 16 pcs. |
| 100×150×6000 | 0.09 m 3 | 11 pcs. |
| 150×150×6000 | 0.135 m 3 | 7 pcs. |
| 100×180×6000 | 0.108 m 3 | 9 pcs. |
| 150×180×6000 | 0.162 m 3 | 6 pcs. |
| 180×180×6000 | 0.1944 m 3 | 5 pieces. |
| 100×200×6000 | 0.12 m 3 | 8 pcs. |
| 150×200×6000 | 0.18 m 3 | 5.5 pcs. |
| 180×200×6000 | 0.216 m 3 | 4.5 pcs. |
| 200×200×6000 | 0.24 m 3 | 4 things. |
| 250×200×6000 | 0.3 m 3 | 3 pcs. |
Table of the amount of unedged boards in 1 cubic meter
When roundwood is harvested, first of all they try to accurately calculate its cubic capacity.
The measurement is made in the upper cut, where the diameter will be slightly smaller. When measuring trunks that have a cross-section other than round, they try to take measurements along the narrowest section, passing through the center of the annual rings of the wood.
This technique is used because it allows you to most accurately estimate how much you can get from one log. edged lumber, having the greatest value in woodworking. Obviously, they will be cut based on the diameter of the top cut.
For the same reason, the ridge part of the trunk, where the difference between the larger and smaller cut diameters is large, is preferred to be discarded and not used in the preparation. In any case, the sawmill will accept timber from the top cut.
When determining the length, measurements are made with an accuracy of 10 cm, and the length is rounded down. Such precision is achieved due to the fact that when felling logs, two cuts are usually made - one higher, the other lower. First they do the bottom one, then the top one - on the other side. falls in the direction where the top of his head leans. The cuts are made so that the bottom one is on the side where the trunk should fall.
In this case, the upper cut is made from the other side, standing in the direction opposite to the most likely fall. During subsequent sawing, the whip is usually cut with a saw into one cut, but often a cutting error is allowed - it can go slightly obliquely, which is why there is such a large error.
Calculation according to cubic meter
In accordance with it, you can determine the volume of each log by taking measurements and selecting the value from the table. In the table, the diameter of the trunk is in increments of 1-2 cm, and the length in increments of 10 cm. Of course, using the entire cubature table is not entirely convenient.
This table provides data for the most common top cut diameters and lengths. Usually it is necessary to calculate the volume for logs up to 6 meters long. It is logs of this length that fit into most standard bodies of ordinary ones, not specialized ones like timber trucks or timber trailers for tractors; it is in sizes up to 6 meters that logs are bucked.
Naturally, when timber is delivered to a sawmill, there is no talk of any “approximate” calculations, and it is necessary to apply the full GOST in the final calculation - after all, this is both sawmills and money for foresters who love accurate calculations.
Calculation by formula
V=πd²l/4, where d is the diameter of the trunk 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.
This is convenient when you don’t have GOST at hand, but only have it. With large volumes of work, even from three or four machines, calculating in this way will take a lot of time, in addition, this technique is not standardized and is not an argument in financial disputes.
Read also:
-
A DIY chainsaw sawmill will help you solve... -
-
How to calculate the square footage of a roof: calculation rules,…
Debarked round timber (logs) is a very popular material. Unlike a rounded log, a debarked log has a significant advantage, because it retains the top splint layer, which effectively protects the inner wood from various pests and bacteria. Thanks to this, a log house made from debarked logs will last much longer and will require less costs for antiseptics than a house made of rounded logs. When purchasing logs for building a house, it is necessary to determine not only their quantity, but also their volume, because all suppliers sell logs by volume. You can convert quantity into volume either manually, remembering school lessons in algebra and geometry, or using tables or special tools. In this article we will talk about various techniques calculation, which will help you correctly determine the required volume when ordering and purchasing logs.
Calculating log volume manually
The methodology for determining the volume of a log is described in detail in two documents adopted back in the Soviet Union - GOST 2292-88 And GOST 2708-75. Since then, no changes have occurred in this technology, so all the recommendations set out in GOSTs are still relevant today. Here are the basics for both measuring an individual log and determining the volume of stacked logs:
- the diameter is determined by the upper (thin) edge of the log using mechanical measuring forks (analogous to a caliper);
- the diameter of the top part of the log is measured twice, with a deviation of 90 degrees; if the values differ, then they are averaged;
- when determining the diameter of the log, the thickness of the bark is not taken into account;
- diameter is rounded to half a centimeter;
- the volume of logs for building houses is determined by multiplying the average volume of a log by the number of logs in the stack;
- Measuring the volume of logs by multiplying the height, width and length of the stack is unacceptable.
After determining the diameter and length of the log, its volume is calculated using the formula. For example, the volume of a log 10 meters long and 15 centimeters in diameter is 0.176 m³. Therefore, there will be 5.5 logs in one cubic meter.
Video - Calculator - cubaturnik
Determining the volume of a log using a computer caliper
The computer caliper determines the volume of each log by measuring the diameter and entering the length. Using this tool allows you to avoid tedious work with tables and numerous calculations. After determining the thickness and entering the length of the log, the fork independently determines its volume and displays the data on the display. Because of high cost This tool is used only at wood processing enterprises.