Hello dear readers! In this article, I decided to use previously published information and online calculations for calculation of a canopy from metal structures.
A carport can be used for a variety of purposes, but let it be a carport.
Initial data:
- city of construction - Grodno ( - Republic of Belarus, Grodno region)
- size in terms of 3x6 meters
- load-bearing structures (rack - profile pipe, beam - I-beam, girders - channel)
- height to the bottom of the beam - 2.7 meters
- roof slope - 10%
- roofing material - profiled sheet NS35x1000x0.5 (weight 1 m2 - 5.4 kg)
- steel class C255
So our main task- this is to determine the size of the section of our load-bearing structures. We will collect loads for each structure and calculate separately. We will calculate from top to bottom., i.e. immediately runs, then beams and racks. This is done so that when calculating the racks, we already know the weight of the overlying structures (beams and girders).
Run Calculation
We will rely on the run for strength and deflection
To calculate the runs, we will need to know the linear uniformly distributed load on it and the design scheme.
The run will be welded at the place of laying to the beam, which means that it will be a hinged joint and a design scheme, respectively, “hinge-hinge”.
Loads from the weight of the profiled sheet, the own weight of the run and the snow load will act on the run.
The figure shows the load area of the calculated run.
In order to translate the load per square meter into a linear one, we will need to multiply it by the width of the cargo area. = 5.4 kg/m2 * 1.003 m = 5.42 kg/m
To obtain the calculated load, we multiply the standard load by the load safety factor (for metal structures it is 1.05). = 5.42 kg/m * 1.05 = 5.69 kg/m
Then, in the same way, we find the calculated linear load from snow (the reliability factor for snow load is 1.4):
50 kg/m2 * 1.003 m * 1.4 = 70.21 kg/m
The final value of the linear load will be the following:
5.69 kg/m + 70.21 kg/m = 75.9 kg/m
Then, choosing one or another section with a small margin (the online calculation already includes the load from the own weight of the structure).
As a result of the strength calculation, we got channel No. 5P according to GOST 8240-89.
Now let's calculate this run for deflection. Looking at SP 20.13330.2016 "Loads and Impacts", we see that the maximum deflection for our 3-meter run is calculated as l/150=3000/150=20 mm.
Substituting all the values found into the deflection calculator, we see that the deflection turned out to be 18.9 mm and it is not more than our maximum allowable deflection of 20 mm.
So we conclude that a run from channel 5 suits us both in terms of strength and deflection.
Calculation of an I-beam
We will calculate the beam that lies on axis 2, because the cargo area, and, consequently, the load, will be the largest for it.
The beam will rest on the overlay at the end of the rack. The trim is welded to the post and the beam will be welded to the trim. This means that the support is again hinged and the design scheme "hinge-hinge".
Loads that will act on the beam:
- snow load = 50 kg/m2 * 3 m * 1.4 = 210 kg/m
- load from profiled sheet = 5.4 kg/m2 * 3 m * 1.05 = 17.01 kg/m
- load from the weight of the girders (12 meters of the girders fall into the cargo area, the mass of one meter is 8.59 kg) = 12 m * 8.59 kg / m * 1.05 = 108.23 kg. We write this load as linearly distributed over 3 meters : 108.23 kg / 3 m = 36.08 kg/m.
- load from the own weight of the beam (taken into account in the online calculation)
The final load on the beam will be:
210 kg/m + 17.01 kg/m + 36.08 kg/m = 263.09 kg/m
Next, again, according to ours, we select the section:
According to the calculation, we see that this beam passes with a good margin in terms of strength. Now let's calculate it for deflection (the maximum allowable deflection for a beam equal to 3m, again, is 3000/150 = 20 mm).
Based on two calculations, it can be seen that the beam 10B1 passes with a good margin. In general, the cross section can be reduced, but as an example, we will leave this beam
I got an I-beam No. 10B1 according to STO ASChM 20-93.
Calculation of a rack from a profile pipe
From all the racks, we will calculate the most unfavorable (the highest and most loaded). This will be the 2-B pillar. Its height will be 2700 mm, and the cargo area will be 3 m * 1.5 m = 4.5 m2.
This cargo area will be affected by concentrated design loads from:
- profiled sheet = 5.4 kg / m2 * 4.5 m2 * 1.05 = 25.52 kg
- weights of purlins = 6 m * 8.59 kg/m * 1.05 = 54.12 kg (6 meters of purlins fall into the cargo area)
- the mass of the beam (it can be calculated in, given the fact that 1.5 meters of the beam falls into the cargo area) \u003d 11.92 kg * 1.05 \u003d 12.52 kg
- snow load = 50 kg/m2 * 4.5 m2 * 1.4 = 315 kg
- load from the own weight of the rack (we will take 3% of the total load on the rack)
The final load on the rack will be as follows:
(25.52 kg + 54.12 kg + 12.52 kg + 315 kg) * 1.03 = 419.4 kg
Convert to kilonewtons: 419.4 kg * 10 N / kg / 1000 \u003d 4.194 kN.
From below, the rack is welded to a plate, which is attached to concrete with 4 anchors, so the connection will be hinged, and on top, as we have already found out, it is also a hinged connection with a beam. This means that the design scheme will be "hinge-hinge".
Next, on ours, we calculate the section of the rack from the profile pipe, for example, 40x1.5:
Based on the calculation, it can be seen that the 40x1.5 rack does not pass through flexibility (flexibility formula = calculated_length / radius_of inertia), which means that it is necessary either to reduce the calculated length of the rack by adding ties in two planes, or to increase the radius of gyration by increasing the cross section. We will increase the cross section to 50x2.
As can be seen in the figure, the profile pipe section 50x50 and wall thickness 2 mm.
Spatial rigidity
Even if our frame will not be sheathed on all sides, and, therefore, will not significant wind loads, we still have to take care of spatial rigidity of the canopy.
To do this, in both directions we will arrange connections from a profile pipe (the same as used for racks). Along axes A and B there will be a cross connection, and along axes 1, 2 and 3 we will put a horizontal connection, for the normal passage of the car.
To simplify the understanding of many calculations, we neglected the following things:
1. Wind load: if the canopy is not lined on the sides, the wind load will only affect the roof of the canopy, but with a slight slope it will be negligible.
2. When calculating the girders and beams for deflection, it was necessary to set the standard load, but it will not be worse from the calculated one.
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A canopy cannot be called a simple design, therefore, before purchasing a certain amount of material, you will need an accurate estimate. The supporting frame structure will have to "survive" any load. Any precipitation, strong wind will overwhelm the canopy if the calculations are incorrect.
Therefore, for a professional calculation, you will need the help of a design engineer who will calculate the effect of the snow load, calculate the trusses and provide you with drawings of the canopy. Calculating a canopy is even more difficult when it is a separate structure, and not an extension to the house.
Since the street simplified roof consists of pillars, logs, trusses and coatings, these materials will have to be considered.
pillars
When calculating these supporting elements, the height of our canopy and the number of columns for support are taken into account. For example, when planning a structure of 2-5 meters, a thick pipe from 60 to 80 mm in cross section is used. If the dimensions of the canopy are large, then, as an option, in order not to increase the number of pillars, a 100x100mm pipe is used
crate
The distance between the profiles of the sheathing fabric is calculated from the load parameters and the selection of sections.
Calculating the load on the frame trusses and the supporting structure will help you make your canopy more stable even in winter, when the load from wet snow can reach 3.5 tons.
Farm from a profile pipe
If you have planned an arched canopy, then you cannot do without trusses. Farms are structures that connect logs and support pillars, they determine the width and dimensions of the canopy.
Canopies from metal trusses are more difficult to build than any frame. But if you properly mount this design, everything will be very reliable. The correct frame distributes the load along the pillars and lags, preventing the destruction of the hinged structure.
Farms are almost always made of profiled pipe, which is considered the most durable and is best suited for installing polycarbonate on the crate. The shape of the truss structure can be different, as well as its size.
The most important calculation of trusses is accounting for material and slope.
For example, for a shed with a slight slope, an asymmetric truss shape is used, if the angle of the structure is small, then trapezoidal trusses can be used. The larger the radius of the arched structure, the fewer options that snow will linger on the roof. Therefore, there will be a large bearing capacity of the farm.
For the calculation, sometimes special programs are used; in this case, you can not do without a calculator.
When thinking about how to build a canopy, it is useful to consider ready-made manufacturing schemes from a photo; there you can see approximate calculations for any form of canopy.
Approximate calculation for flooring up to 4 meters high
If you have chosen a simple form of a canopy with a house with a width of 6 by 8 meters, then your calculations will be as follows:
- The step between the supporting pillars (racks) is 3 meters from the end, 4 meters on the side.
- The number of metal pipe posts is 8 pieces.
- The height of the trusses under the slings is 0.6 meters.
- Roof sheathing: profile pipes 12 pieces with dimensions 40x20x0.2.
Sometimes you can save money by reducing the amount of material. For example, instead of six racks, install four. You can also reduce the number of trusses or reduce the frame crate. Only it is not desirable to allow the loss of rigidity, as this will lead to the destruction of the structure.
Before proceeding with the construction of a canopy, it is necessary to determine its functionality, this will help to set the dimensions of the building. Next, you need to make a drawing, which will reflect the main components and dimensions of the structure. On this basis, loads are calculated, the shape, material, dimensions of the supporting structural elements - supports, truss systems, roofs are set, and the method of fastening is determined.
The strength, safety, and reliability of the structure depend on the correct calculation. In the article we will tell you step by step how to build a canopy with your own hands, photos, drawings, formulas will help to clearly explain the important design points.
How to make a canopy from corrugated board with your own hands, drawings with dimensions of the main elements of the building
What is required for the drawings and calculation of the canopy
A canopy is a simple architectural structure consisting of two main structural elements: supports (frame) and a roof. For drawings and calculations, the following data will be required:
- form of support of the canopy;
- functionality, based on this, the size of the building is determined;
- materials;
- tables of wind and snow loads in the region;
- type of truss system.
In order not to get confused in formulas and engineering calculations, it is recommended to use a special program or an online calculator for the calculation.
Canopy to the house, projects-photos of typical metal structures
Drawings depending on the location of the canopy
To draw up drawings and further calculation, first of all, it is necessary to determine the place of construction, the form of support depends on this:
- Stand-alone - on an independent foundation with supporting vertical pillars around the entire perimeter.
- Beam-supporting - extensions to the building: one side of the canopy stands on poles, the other rests on a horizontal beam fixed to the wall to evenly distribute loads along the supporting structure.
- Cantilever-supporting - extensions to the building, but here the support falls on brackets or mortgages arranged in the bearing wall.
- Cantilever - small canopies over the entrance to the house, supported by mensols or mortgages.
Drawing of a canopy from a profile pipe, parking for a car on independent supports
Dimensions and functionality
The functionality of the building is very important for drawing up drawings and competently calculating the canopy. Consider typical projects of different types of structures.
Canopies over front door
The calculation of cantilever visors is carried out based on the dimensions of the porch. According to the standards, the upper platform should be one and a half times the width of the door, the average door width is 900 mm, we make the calculation: 900 * 1.5 \u003d 1350 mm - the optimal depth of the roof above the entrance. The width of the canopy depends on the width of the steps + 300 mm on each side.
Drawing of the visor above the front door
Cantilevered canopies are usually arranged over the area of the entire porch and cover the steps. The depth of the roof is calculated based on the number of steps, the average depth of which according to SNiP is 250-320 mm, plus the upper platform. The calculation of the width of the canopy above the porch is regulated by the standard width of the steps - 800-1200 mm + 300 mm on each side.
We calculate the dimensions:
- Standard cantilever visor - 900-1350 mm by 1400-1800 mm.
- Cantilevered canopy over the porch, an example of calculation for 3 steps and a platform: depth (900/1350 + 3 * 250/320) = 1650 - 2410 mm, width 800/1200 + 300 + 300 = 1400-1500 mm.
Drawing of a beam-supported structure with an asymmetric roof
Verandas and terraces - drawing and calculation
Verandas and terraces are located along one of the walls of the house, so beam-support and cantilever-support structures are relevant here. The minimum depth is 1200 mm, the optimal one is 2000 mm, just at the installation distance of the support post.
Drawing of an attached canopy with a support beam
The calculation of the roof along the perpendicular is 2000 + 300 mm, but a flat roof is only suitable for areas with a minimum amount of precipitation, in other regions it is recommended to make a slope of 12-30 o. To calculate the depth of the roof of the canopy, the Pythagorean theorem is required: c 2 \u003d a 2 + in 2.
Calculation example:
If the slope angle = 30 o, the leg adjacent to it (the depth of the roof of the canopy along the perpendicular) is 2300 mm, the second angle is 60 o. Let's take 2 legs for X, it lies opposite the angle of 30 o, and according to the theorem it is equal to half of the hypotenuse, hence the hypotenuse is 2 * X, we substitute the data into the formula:
(2*X) 2 = 2300 2 + X 2
4*X 2 = 5290000 + X 2
4 * X 2 - X 2 \u003d 5290000
X 2 (4-1) = 5290000
3*X 2 = 5290000
X 2 \u003d 5290000: 3
X 2 \u003d 1763333, (3)
X \u003d √1763333, (3) \u003d 1327 mm - the leg, which will be adjacent to the wall of the house.
Calculation of the hypotenuse (the length of the roof with a slope):
C 2 \u003d 1327 2 + 2300 2 \u003d 1763333 + 5290000 \u003d 7053333
С = √7053333 = 2656 mm
From here we calculate the total height of the canopy: 2000-2400 mm - this is the minimum ergonomic height, we calculate taking into account the slope: 2000/2400 + 1327 = 3327/3737 mm - the height of the canopy wall near the house.
How to build a free-standing shed canopy from a metal profile with your own hands, frame and truss drawings
Attention: In the drawing, it is necessary to take into account: the smaller the slope of the canopy, the lower its total height. The parameter is especially relevant if windows and doorways are provided in the wall of the house.Car parking - standard calculation and drawing
Parking lots for cars are arranged as free-standing buildings or beam (cantilever)-support type. If you plan to make a carport with your own hands, the drawings are made taking into account the class of the car. Parking dimensions in width are calculated: car size + 1.0 m from each side, for 2 cars + 0.8 m between them is taken into account.
Drawing of a small structure for a parking lot or utility block
An example of calculating a canopy for a middle-class car, width - 1600 -1750 mm, length - 4200-4500 mm:
1600/1750 + 1000 + 1000 = 3600/3750 mm - canopy width;
4200/4500 + 300 +300 = 4800/5100 mm - ergonomic length so that precipitation does not flood the site.
Calculation of the width of the canopy for two cars:
3600/3750 + 800 = 4400/4550 mm.
Often, an arched polycarbonate canopy is built for a car with their own hands; drawings of a convenient design on a pile foundation are presented below.
An example of how to build a carport with your own hands, a drawing of an arched metal structure with a polycarbonate roof
gazebos
Sheds for recreation are usually arranged in the depths of the site, these are free-standing structures on a pile, columnar, strip, slab foundation. The choice of base depends on the dimensions of the structure and the nature of the soil, this must be reflected in the drawings.
The average size of the gazebo is 3 * 4, 4 * 4, 4 * 6 m. To independently calculate the design and make a drawing, you should take into account the following parameters:
- For a comfortable stay for 1 person, 1.6-2 m 2 of floor space is needed.
- If a brazier is located under the canopy, then it is recommended to leave a free area 1000-1500 mm wide between the stove and the recreation area.
- Comfortable seat width 400-450 mm.
- Ergonomic table size 800/1200 by 1200/2400 mm, individual calculation is made taking into account 600-800 mm for 1 person.
Drawing of a free-standing canopy-arbor made of wood
Basic Rules for Canopy Drawings
When drawing a canopy, it should be noted that the minimum height of the structure (from the ground to the lower edge of the roof slope) is 2000-2400 mm, the maximum depends on the type of roofing system.
Roof - what to consider in the drawings
Above, we discussed in detail how to calculate a shed roof for a canopy; a gable roof is calculated according to the same principle. The angle of inclination depends on the choice of roofing material and the climate in the region:
- 45-60 o - snowy areas;
- 9-20 about - windy areas;
- 15-30 o - the universal slope of the slopes, almost all types of roofing materials are suitable: corrugated board, roofing material, soft tiles, slate, polycarbonate, galvanized iron, metal tiles, ondulin, etc.
One- and two-pitched roofs are optimal for all types of canopies made of wood, brick, concrete, stone, for forged products. For welded metal structures, more and more, they arrange an arched roof. In order to correctly calculate a canopy from a metal profile with your own hands, the drawings must reflect, in addition to the size of the building, the radius of the roof arc.
In fairness, let's say that welded and prefabricated metal structures are crowned not only by an arched roof, but also by other types of trusses. The calculation of the truss for the canopy, the calculation of the structure of the canopy depend on the overall dimensions of the building. It is very difficult to calculate the rafter system on your own, so it is better to use an online calculator, contact a specialist, or take as a basis a ready-made project of a standard truss, as in the photo below.
An example of how to weld a truss for a canopy, drawings of typical structures
materials
Here are the standard materials that are suitable for all standard drawings. For wooden awnings:
- Supports, piping around the perimeter - profiled or glued timber, 100 * 100, 150-150 mm, rounded log with a diameter of 200 mm. The distance between the posts is 1.5-2.0 m.
- Rafters - edged board 150 * 40 mm.
- Lathing - rail 15-20 * 40, unedged board, moisture resistant plywood, OSB.
Drawing of a wooden canopy with estimated dimensions of the main components of the structure
Metal canopies:
- Vertical racks - a round pipe with a diameter of 100-150 mm, a profiled pipe 50 * 50, 80 * 80 - for small structures up to 6 m, 100 * 100, 150 * 150 * - for large buildings.
- Farm for a canopy, frame (upper and lower belt) - professional pipe 40 * 40, 40 * 60, 30 * 60 mm - depending on the size of the structure, wall thickness 2-3 mm.
- The slopes and stiffeners of the farm are metal profiles 50 * 25, 40 * 20, 25 * 25 mm, thickness - 2 mm.
- Lathing - corrugated pipe 20 * 25, 20 * 40 mm.
Drawing of a standard visor
Instructions on how to design a polycarbonate canopy with your own hands - drawings, photos, calculations of a private parking lot
Usually, under a polycarbonate roof, a frame is made for a canopy from a profile pipe with an edge of 100 * 100 mm. For an accurate calculation, snow and wind loads should be taken into account. To calculate farms for a canopy with your own hands, you will need the following data:
- span size;
- drawing with the general dimensions of the farm;
- design resistance of the metal, Ry= 2.45 T/cm 2 ;
- type of attachment of nodes (bolted, welded);
- 01.07-85 SNiP load and impact;
- P-23-81 SNiP steel structures.
Calculation of a farm from a profile pipe for a canopy:
Arched truss for a polycarbonate canopy, the radius is easier to calculate graphically
The span between the support pillars is 6000 mm, the distance between the extreme nodes is 6500 mm, the height between the lower and upper chords is 550 mm, the boom is f = 1.62 m, the radius is 4100. Hence the length of the profile pipe of the lower chord:
MH = π*R: 180, where
MH - belt pipe size from below,
R - arc radius,
MH \u003d 3.14 * 4.1 * 93.7147: 180 \u003d 6.73 m.
Upper chord pipe length:
MH \u003d 3.141 * 4.1 * 105.9776180 \u003d 7.61 m.
The length of the rods on the lower chord at 12 spans:
L = 6.73:12 (number of spans) = 0.56 m.
According to the calculations, this is how the project of a canopy of metal structures will look like
For the roof of a polycarbonate canopy, you will need to calculate the distance between the crate. Calculations will require SNiP, the law of theoretical mechanics and strength of materials, therefore we offer a ready-made table with the calculations of specialists.
Table of dimensions of the shed of a canopy from a metal profile for different regions
X
Y
Z
Visor material width- allows you to determine the width of the required cover material for covering a semicircular canopy or canopy. Using the function of calculating this parameter, you can choose the optimal dimensions of the visor to maximize the use of material of factory dimensions. Knowing visor area, You can purchase exactly as much material to cover the structure as you need and not overpay for the surplus. Please note that the calculator only calculates the parameters of the roofing material for the visor and does not calculate what and how much is needed for the manufacture of the frame and its fastening (metal profile, board, concrete, hardware).
X- the width of the visor is the distance between its extreme points along the facade. To protect against precipitation, the width of the visor must be chosen slightly larger than the size of the front door. If possible, you should make a visor for the entire width of the porch with a margin of 500 mm on each side. However, it should be remembered that the larger the surface of the canopy, the more snow will be on it in winter, which means that the design must be reliable. When choosing the width of the visor, it is necessary to take into account SP 20.13330.2011 "Loads and impacts".
Y- the height of the visor (meaning the value of the height of the segment of the semicircular visor, and not the installation level relative to the threshold of the house), the larger this parameter, the greater the consumption of material for covering.
Z- the length of the canopy - the distance from the facade can be different, depending on your wishes and the architecture of the house. The minimum rain protection length is 700 mm. You can focus on the size of the porch with a small margin. Please note that if the length of the canopy exceeds 2000 mm, then additional supports must be placed under the free edge.
By checking the “Black and white drawing” item, you will receive a drawing that is close to the requirements of GOST and will be able to print it without wasting color ink or toner.
Calculation results and their use:
Visor material width- allows you to determine the width of the required cover material for covering a semicircular canopy or canopy. Using the function of calculating this parameter, you can choose the optimal dimensions of the visor to maximize the use of material of factory dimensions. Calculating visor area, You can purchase exactly as much material for the canopy arch as you need and not overpay for the surplus. Please note that the calculator only calculates the parameters of the roofing material for the canopy arc and does not calculate what and how much is needed for the manufacture of the frame and its fastening (metal profile, board, concrete, hardware). If desired, you can specify a height equal to a small number, which will allow you to calculate a flat canopy.
Calculations are the forerunner of the construction of a stationary canopy. The calculation of the canopy is necessary in order for the structure to be reliable, withstand its own weight, as well as the loads created by wind and snow. Within the framework of this publication, we will only talk about the drawing and calculations of various parts of the structure using the example of a polycarbonate car canopy. The entire package of project documentation is much larger and a separate article will be devoted to it.
What should be kept in mind when preparing a project?
Before you make a drawing of a polycarbonate canopy, you need to decide on the general design and design concept, namely how the structure will look, what shape it will have, what it will be intended for. Next, you need to draw a sketch of the structure, where you indicate the general dimensions of the polycarbonate canopy (length, width and other parameters) and its main elements. At the next stage, you can prepare a drawing of a polycarbonate carport, while remembering.
Note! When preparing a drawing of a structure, it is necessary to find and attach to it technical data on the materials used.
We calculate the farm arch type
We have a sketch of a large carport made of metal, designed for 2 cars with an arched roof (arc) covered with sheets of cellular polycarbonate. The width of the canopy from support to support is 5.8 meters, the width of the arched truss (arc) should be 6 m. Let's calculate the section of the profile that will be used in the manufacture of the arched ceiling.
ɒ pr \u003d (ɒ 2 + 4t 2) 0.5 ≥ R / 2, we will decipher this formula:
- ɒ is the standard voltage;
- R is the strength of iron C235, about 2440 kgf / cm 2;
- t is the tangential stress.
Now, by successively selecting indicators, we can calculate the profile of a suitable section so that it can withstand the desired loads. We take a square profile pipe 30x30x3.5 mm with a cross section of 35 mm 2 with a moment of inertia of 3.98 cm 4, a load coupling coefficient of 0.5, the estimated load on the locking part of the arch is 914.82 kgf.
All the necessary data for the calculation has been collected, the formula is there, now it remains to substitute the data into the formula and get the calculation of the load on the arched truss (arc) of the polycarbonate car canopy.
ɒ pr \u003d ((914.82 / 3.5) 2 +4 (919.1 * 1.854 / ((0.35 + 0.35) 3.98) 2) 0.5 \u003d 1250.96 kg / cm 2 .
What does it mean? And this means that if we weld or twist a six-meter arch from a 30x30x3.5 mm profile, it will fully withstand its own weight and the weight of the roofing material, that is, cellular polycarbonate. There is even a decent supply.
We calculate the supporting part of the structure
Next, you need to calculate what will be the supports of the polycarbonate car canopy. There is a special technique by which it is customary to calculate steel columns; without it, an adequate calculation of the canopy is impossible. Let's apply the formula:
F=N/ϕR Let's decipher the formula:
- F - section of a square pipe that can be used as a support;
- ϕ is the coefficient that determines the buckling;
- R y - the value of the resistance of the material.
In order to make calculations, you will have to find data on the resistance of materials. In our case, the resistance of steel square pipes 70x70, 80x80, 100x100 mm, the values found will need to be compared with the calculation results and conclusions drawn. We make calculations:
F=3000/(0.599*2050)
As a result, we get a value of 2.44 cm 2, which must be rounded up. As a result, the value on which we should rely when searching for a suitable profile is 2.5 cm 2. These indicators correspond to a square steel pipe 70x70x2 mm, there is even a small margin.
Roof loads from snow and wind
It is possible to answer the question of how to calculate a carport only if you calculate the load-bearing structures of the structure and the load on the roof from snow and wind. We have dealt with the calculation of load-bearing structures in general terms. Now we need to solve the problem with the loads from wind and snow.
To get the data you need to calculate, you need to look at the average wind and snow loads in your area. You can find such information in the relevant SNiP.
For example, let's take the value of the wind load 23kg / m 2. But in our case, this value will not work because 23kg / m 2 is defined for buildings and structures that have walls. The carport has supports, arches, lintels, a run and a roof, so the pressure will be exerted only on them. We determine the average wind effect on the canopy, we get 0.34 with a height of supports over three meters, a value from 0.34 to 0.75 kg / m 2. We calculate the maximum load created by the wind on the entire structure: arcs, supports, purlins, roofs.
W m \u003d 23 * 0.75 * 0.34. The result is a value of 5.9. Now we calculate the load created by the snow cover. These loads in different regions of the country differ, and differ significantly. In mountainous areas, such a load can be more than 600 kg / m 2, but we will take a more modest figure of 180 kg / m 2 (Moscow region) as an example.
To calculate the maximum load on the canopy, you need to multiply 180 by the value of the conversion factor, which has yet to be obtained. The figure below shows the calculation of the snow load on the canopy.
The maximum load of snow on the canopy was calculated. Now it remains for us to find out the inertia index for the roofing material we have chosen. You won't find such data in the usual commercial description of the material, but it is in the technical description. For example, for cellular polycarbonate with a thickness of 12 mm, inertia is 3.41 cm 4. Find a material with a calculated value or more than that and you can safely put it on the roof of a car shed. You can read more about what you can make a roof for a canopy in the article.
In conclusion, we note that the designs of carports for cars are not so complicated, however, one cannot be free to build such structures. First, the general structure of the canopy must be drawn on the sketch, indicating the length of the structural elements, their diameter and other simple parameters. After that, you can proceed to the calculations and the manufacture of the drawing. In the process of work, you will have to calculate the parameters of the arched truss (arc) and much more. If you feel that this work is beyond your power, contact a specialist. Good luck!
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