Shell and foam block
Analyzing which is better - a shell rock or a foam block, their general and individual qualities will be compared.
Comparison of shell rock and foam blocks with other materials
Since the foam block is an artificial material, its qualities completely depend on the manufacturer. All data taken for comparison assume that the foam blocks meet the requirements of GOST 25192-82 and GOST 21520-89.
Main disadvantages and advantages
Shell or foam block, which is better? To answer, you need to know the features of each specific case, not forgetting to carefully study all the main parameters.
Advantages
The main advantages of natural stone are its environmental friendliness and durability:
- Shellfish is composed of the mineral remains of dead sea creatures and sedimentary rocks. It is very rich in iodine - the inner walls of this material have a beneficial effect on the thyroid gland. Prevents diabetes mellitus.
- The layers from which the stones are cut were formed millions of years ago.
By the time it entered the construction site, the shell rock had survived every possible cataclysm thousands of times. Its durability has been proven by nature.
These shell rock walls have withstood more than one siege
The ability to leave the most original stones as part of the design gives in the comparison "which is better than a foam block or a shell rock?", A significant score for a shell.
But the foam block also has its advantages. Produced by prescription, it has clear characteristics that allow for engineering calculations.
More accurate geometric dimensions make it much easier and faster.
Both materials have high noise and heat insulation characteristics.
Flaws
The main common drawback is low strength, but the foam block may still be at the production stage. In this case, its flexural strength becomes several times higher.
When deciding - shell or foam block, which is better to choose for load-bearing walls, this factor plays a very important role.
The second problem is the high degree of moisture absorption. Voids that retain heat well are just as well filled with liquid.
High percentage of shell rock fighting in the career
The foam block splits no worse than shell rock!
Important! The strength of one package of foam blocks is usually stable. To check it is enough to try to break one. If it breaks with difficulty, the halves will be needed in the masonry. If it is easy, it is better to return all the packaging to the seller.
This method is not applicable to shell rock, since the characteristics may differ within the same stone. For such a check, you need to break all the blocks.
Production technology
Foam blocks are made from a mixture of cement and sand, and the shell is cut from the strata along the shores of the southern seas. It is this difference that gives rise to factors influencing the choice: which is better, a foam block or a shell rock?
Rakushnyak
The available deposits of shell rock are located in places where the sea receded from its boundaries thousands of years ago. The location of the quarries is the coast of the Black, Azov and Caspian Seas.
Until the mid-20th century, the stone was carved and hollowed out by hand. Impact loads resulted in frequent block cracking.
Sawing machines are now operating in the quarries, which neatly cut products from the seams.
Foam block
The method of making foam blocks is very simple.
- Cement, sand, foaming agents and water are mixed in a special high speed mixer.
- The liquid mixture is poured into molds.
- After the solution hardens, the blocks mature within 4 weeks.
This availability of production leads to the appearance of frankly bad products on the market.
One person can easily complete the entire process
Advice! No need to buy products of unknown origin. The presence of certificates does not guarantee the good faith of the manufacturer. But, at least, it gives a chance to buy foam blocks of normal quality.
Specifications
In terms of technical indicators, in addition to ecology, the foam block is superior to the shell.
Rakushnyak
Depending on the region of production, quarry, formation and many natural factors, the parameters of shell rock are a very relative concept. Such instability is a significant disadvantage in comparison, which is better, a foam block or shell rock.
The difference in the density and strength of the shell rock at the place of origin
Standard cut blocks have dimensions 380/180/180. Unfortunately, these dimensions are respected within the range of 20-30 mm.
- The substance of the blocks, which has hardened for thousands of years, does not react with other materials.
- Deep pores are the basis for the setting of the plaster.
Shell rock is subdivided according to strength grades.
- M15- used only as insulation.
- M25- construction of one-story buildings is possible.
- M35- allows the construction of load-bearing walls up to 3-4 floors.
Dimensions and weight of shell rock by brand
Externally, stones of different grades can be distinguished by the number of pores and color - the fewer cavities and whiter, the stronger the block. At the same time, there are solid blocks with large pores. Nature doesn't like to abide by standards.
Foam block
Produced artificially, it has a wider range of characteristics:
- In terms of strength, the foam block can significantly surpass shell rock. However, the insulation will deteriorate and the weight of the unit will increase.
Characteristics of foam blocks
- All parameters of the selected brand of foam concrete are stable for each block.
Blocks of the same batch are like twins
- Foam blocks have a wide range of sizes.
Sizes of foam concrete blocks
From the point of view of convenience and speed of work, as well as the accuracy of preliminary calculations, foam blocks clearly benefit.
Application
The advantage of the shell is the possibility of using the leftovers for design purposes.
Rakushnyak
The main purpose is construction, the originality of each stone provides many additional opportunities.
Blocks are easy to cut into decorative tiles or other parts for indoor and outdoor use.
Arrange an exclusive landscape with your own hands.
Shellfish in the landscape Tip! Constructions made of shell rock are not load-bearing; they can be placed on a clay, environmentally friendly, mortar. The amount of water depends on the parameters of the clay.
Foam block
These blocks are used for the construction of internal partitions and external load-bearing walls.
Shell rock has a wider range of applications. But it is more difficult to build from it, so the price of work will be higher and the construction period will increase. You can find out more interesting facts by watching the video in this article.
Shellfish video:
Video about foam blocks:
Price
Since the foam block can be produced in any region, its cost is stable and depends on the density grade.
In places of extraction, shell rock is one of the cheapest building materials. Its price increases with distance from the quarry. This feature can be decisive in comparison - shell or foam block, which is better for home.
Shell rock, shell rock are the names of sedimentary rock, a type of limestone formed from organic remains of marine living organisms, mainly from shells and their fragments. The main constituent of shell rock is calcium carbonate.
The main deposits of shell rock are located in the places of prehistoric seas. As the waters receded over time, the remains of sea creatures that had accumulated on the seabed for millions of years were exposed. Under the influence of natural conditions, the skeletons of prehistoric sea creatures were compressed to the hardness of stone.
Shell rock characteristics
Shell rock is a type of limestone, mainly composed of calcium salts. Its chemical composition, regardless of the deposit, is practically the same.
| Varieties of stone by color | Chemical composition (%) | Density (g / cm3) | Specific gravity (kg / m3) | ||
| CaCO3 | MgCO3 | Insoluble residue | |||
| Yellow and yellowish gray | 90-95 | 3-8 | 2 | 0,8-2,3 | 800-2300 |
| Yellowish gray with a green tint, slightly marly | 84-85 | 5-6 | 10 | ||
| Yellowish gray, slightly sandy | 85-90 | 3-5 | 5-6 | ||
The popularity of shell rock as a building material is due to its strength and attractive structure. Depending on the porosity, there are three types of stone:
- M15 grade is a stone of high porosity and, as a result, low strength. Its color is light yellow. Admixtures of sand in large quantities, which have high thermal conductivity, make the stone "cold". Blocks of stone of this brand are extremely fragile and light, but they are successfully used for the construction of low one-story buildings (garages, sheds, baths, fences, etc.).
- M25 grade is a stone of greater strength and lower porosity. The most common brand in construction practice. Color - light yellow. M25 strength indicators are greater than those of bricks, gas or foam concrete.
- M35 is the highest density shell rock brand. Low porosity provides high specific shell weight and high strength. The stone's yellow-white color, dense structure and low water absorption make it an excellent material for exterior cladding of buildings, giving them a unique flavor. It is also used in the construction of buildings with several floors when laying foundations and arranging cellars. Its density is close to that of concrete.
Extraction and application
Shell rock is one of the few building materials that nature gave us almost ready-made. The extraction of stone consists in cutting geological layers with special machines into blocks of a certain size. The appearance of the stone, even within the same deposit, can change significantly. The stone is easy to saw and work. Depending on the further purpose, the surface of the stone will be simply sawn, polished or slightly rough.
Material advantages:
- relatively small shell rock weight,
- low cost,
- unique texture,
- simple processing and installation,
- excellent adhesion due to the porous structure,
- low thermal conductivity,
- good noise insulation and frost resistance (with proper installation and operation without loss of quality, it can withstand more than 100 seasons),
- does not enter into chemical reactions with other building materials.
Rakushnyak is widely used in low-rise construction, interior and exterior decoration. Looks great in landscaping projects on personal plots (fences, retaining walls, grottoes, fountains, etc.). Polished coquina tiles impregnated with hydrophobic solutions are used as decorative finishes.
How much does 1 cube of shell rock weigh, weight of 1 m3 of shell rock? The number of kilograms in 1 cubic meter, the number of tons in 1 cubic meter, kg in 1 m3. Bulk density of coquina, coquina specific gravity.What do we want to know today? How much does 1 cube of shell rock weigh, weight of 1 m3 of shell rock? No problem, you can find out the number of kilograms or the number of tons at once, the mass (weight of one cubic meter, weight of one cubic meter, weight of one cubic meter, weight of 1 m3) are indicated in Table 1. If someone is interested, you can skim the small text below with your eyes, read some explanations. How is the amount of substance, material, liquid or gas we need measured? Except for those cases when it is possible to reduce the calculation of the required quantity to the calculation of goods, products, elements in pieces (piece count), it is easiest for us to determine the required quantity based on the volume and weight (mass). In everyday life, the most familiar unit of volume measurement for us is 1 liter. However, the number of liters suitable for household calculations is not always an applicable way to determine the volume for economic activities. In addition, liters in our country have not become a generally accepted "production" and trade unit for measuring volume. One cubic meter, or in an abbreviated version - one cube, turned out to be a rather convenient and popular unit of volume for practical use. We are used to measuring practically all substances, liquids, materials and even gases in cubic meters. This is really convenient. After all, their cost, prices, rates, consumption rates, tariffs, supply contracts are almost always tied to cubic meters (cubes), much less often to liters. It is no less important for practical activity to know not only the volume, but also the weight (mass) of the substance occupying this volume: in this case, we are talking about how much 1 cubic meter weighs (1 cubic meter, 1 cubic meter, 1 m3). Knowing the mass and volume gives us a fairly complete idea of the quantity. Site visitors, asking how much 1 cube weighs, often indicate specific units of mass in which they would like to know the answer to the question. As we noticed, most often they want to know the weight of 1 cubic meter (1 cubic meter, 1 cubic meter, 1 m3) in kilograms (kg) or in tons (tons). In fact, you need kg / m3 or tn / m3. These are closely related quantity-determining units. In principle, a fairly simple independent conversion of weight (mass) from tons to kilograms and vice versa is possible: from kilograms to tons. However, as practice has shown, for the majority of site visitors, a more convenient option would be immediately find out how many kilograms 1 cube (1 m3) of shell rock weighs or how many tons weighs 1 cube (1 m3) of shell rock, without converting kilograms to tons or vice versa - the number of tons to kilograms per cubic meter (one cubic meter, one cubic meter, one m3). Therefore, in table 1, we indicated how much 1 cubic meter (1 cubic meter, 1 cubic meter) weighs in kilograms (kg) and in tons (tons). Choose the column of the table that you need yourself. By the way, when we ask how much 1 cubic meter (1 m3) weighs, we mean the number of kilograms or the number of tons. However, from a physical point of view, we are interested in density or specific gravity. The mass of a unit of volume or the amount of a substance contained in a unit of volume is the bulk density or specific gravity. In this case bulk density and specific gravity of shell rock, shell rock. Density and specific gravity in physics are usually measured not in kg / m3 or in tons / m3, but in grams per cubic centimeter: g / cm3. Therefore, in table 1, the specific gravity and density (synonyms) are indicated in grams per cubic centimeter (g / cm3)
As a building material, shell rock is widely used in the coastal regions of southern Ukraine. The local builders have gained extensive experience in the construction and operation of shell rock houses. When starting to build such a house, it should be borne in mind that this natural material has a number of features that distinguish it from artificial building stone (concrete blocks, bricks).
Shell rock has a relatively low density, which is why many are considered not very reliable material for the construction of buildings. Therefore, the construction of a shell rock house needs justification.
As an example, we will give a simplified calculation for a three-story house with shell rock walls and reinforced concrete floors. The thickness of the walls in our calculation is 38 cm (one stone).
It should be noted that the calculation of the house will be made only for the conditions of seismically calm areas. Such areas are marked in blue with the number 5 in the figure below. (the illustration corresponds to the provisions of DBN B.1.1-12: 2006 "Construction of buildings in seismically hazardous areas):
For regions of Ukraine with a higher degree of seismic hazard, the following additions must be made to the design of the future shell rock house:
- device of a reinforced concrete frame and reinforced concrete belts;
- an increase in the thickness of walls and walls;
- the use of higher grades of shell rock;
- reduction of free wall spans.
If all of the above measures are taken, the question of the bearing capacity of the stone will disappear.
V Table 1 the degree of strength of various types of shell rock is given. For our calculations, we will choose the lowest strength, that is, the “weakest” option - “Crimean central and western (fine-pored yellow). Its average strength grade is only 6M.
1.
In our calculations, only the area of the walls will be taken into account, on which reinforced concrete floors will be based. These overlays are highlighted in red in the following figure. This area bears the maximum load. The area of the wall sections on which the floor slabs are pressed is 56 З16 cm². 2. Now you need to calculate the weight of the shell walls with the above-mentioned thickness of Z8 cm. The height of such walls is 9 m (three floors). We multiply the total volume of the walls by the density of shell rock 1150 kg / m3 (taking into account the density of the masonry mortar of 1800 kg / m3) and we get 55 750 kg - this is the weight of the walls of our future house.
3. Next, you need to calculate the weight of three reinforced concrete prefabricated floors (the first floor, the second and the attic floor). For the calculation, we take plates PK-60-12. The standard weight of one such plate is 2100 kg. In total, 18 slabs will be needed for construction. Considering the thickness of the screed (3 cm), the total weight of the floor slabs will be 4Z 905 kg.
4. Then we calculate the roof load on the floor. For the correct calculation of the roof, take the heaviest tile at an angle of 45o. The specific load of the roof projection is 80 kgf / m2. Let's take into account that for Kiev the snow load averages 70 kgf / m². As a result, we find that the load from the roof (6x8 m) on the floor is 7200 kg.
5. The total weight of the house structures = 106 855 kg.
6. Specific load on the bottom row of stone: load on the block = 106 855/56 З16 = 1.9 kgf / cm2.
7. The design resistance to compression of low-strength natural stone masonry of regular shape (our shell rock M6 and mortar for laying M10) = 2.16 kgf / m². (Data taken from SNiP II-22-81 "Reinforced stone and stone structures", table 7).
As we can see, despite a very heavy three-story house with three reinforced concrete floors, a tiled roof and a concrete screed, the maximum load still does not exceed the allowable one - even when using the least durable shell rock.
Of course, our calculation for a shell house was rather simplified. We did not take into account the influence of window and door openings, as well as some other factors. However, even having carried out such calculations, we were able to prove that shell rock is quite suitable for use as a self-supporting building material in the construction of individual houses.
Masonry walls from a shell
It must be remembered that the mortar used for laying shell walls must be plastic. If the solution turns out to be too hard, it will be difficult even for experienced masons to lay the walls of shell rock. The “correct” masonry mortar should not flow, but be easily pliable. To create the optimal solution, you will need:
- PC-400 cement (1 bucket);
- sand (4 buckets);
- water (about 1 bucket).
When mixing such a composition without special additives, it will turn out to be too tough and will be unsuitable for laying shell rock. If you try to make it less rigid by adding water, the solution will begin to delaminate quickly, which will lead to an even greater loss of plasticity. Therefore, when mixing the solution, it is necessary to use a suitable additive that will increase its plasticity characteristics. For this purpose, it is recommended to use the DOMOLIT-TR additive.
To prepare 1 cubic meter of solution, you will need about 0.5 kg of such an additive (the exact dosages are indicated in the instructions). If it is not possible to buy an additive, you can use ordinary liquid soap or dishwashing detergent in the proportion of 10 ml for each liter of water to mix the solution instead.
In the photo you can see a masonry mortar that is optimal in consistency for laying shell rock walls.
If the volume of the masonry is 5,000 shell rock blocks or more, it will be more profitable to use a concrete mixer to mix the mortar. If there is no concrete mixer, the efficiency of the bricklayer brigade will noticeably decrease, since one worker will have to be allocated to mix the mortar. That is, a concrete mixer under such conditions will pay for itself very quickly. In addition, it is useful for preparing mortar and concrete during other construction work.
If the volume of masonry work is planned to be small, the mortar for masonry can be mixed by hand. Kneading is done on regular steel sheet or some other waterproof durable surface.
The set of tools needed to build a shell rock house is as follows:
- Master OK;
- mallet (rubber hammer);
- nylon thread;
- measuring angle;
- high-quality building level;
- buckets for mortar. 
Special attention should be paid to the quality of the building level, since the accuracy of the masonry will depend on it. Don't buy cheap levels with a flimsy bar. As for the buckets, it is also not recommended to save on them: it is better to buy not plastic, but steel buckets that will not break under the weight of the solution.
The laying of the outer walls of the house from shell rock begins from the corners (just like the laying of any other stone). The most time-consuming and responsible work at this stage is to bring the corner of the walls exactly. In our case, this task is complicated by the poor geometry and irregular shape of the shell rock blocks. It is best to entrust the laying of corners to the most experienced bricklayers. And if you decide to carry out the masonry yourself, without having such experience, invite a bricklayer-"consultant" to show you how to use the building level correctly.
This is how the process of laying shell walls looks like:
It is necessary to lay the blocks so that the upper corner of each block "looks" into the thread, but not close to it, but at a distance of 2 millimeters. If the block is attached close to the thread, then it will be pushed through, which will lead to an arcuate curvature of the entire row. By correctly maintaining the masonry along the thread, you will exclude all possible mistakes.
If the walls of the house, as in our case, are laid one stone wide, the masonry should be bandaged through every 4th row of blocks. Bandaging can be done in two ways:
- laying a row of blocks across the wall ("poke");
- placing a 50x50x4 mm masonry mesh in the seam between the rows.
Wall bindings are used to bond the wall of a house, making it more solid and strong. The red arrows in the next photo point to the rows of tied blocks:
EQUIPMENT OF CLOSURES IN THE HOUSE FROM A SHELL
Overlapping in a house with shell rock walls can be done again in two ways:
- on the masonry, directly on the masonry mortar;
- on a reinforced concrete belt.
In seismically safe regions, marked in blue in the first figure in this article, floors can be performed without arranging a reinforced concrete belt (with a wall thickness of one stone, 38 cm). According to SNiP II-22-88, the length of the support surface of the slab must be at least 12 cm.
The structure of prefabricated reinforced concrete floors on the walls of shell stone without a reinforcing reinforced concrete belt is as follows:
The device of a reinforced concrete belt for private residential buildings is necessary for construction in a seismically unsafe area, as well as if the thickness of the walls is insufficient for stability (for example, when laying in half a stone, 18 cm). This is how the belt device looks like (in the diagram: 1 - concrete belt; 2 - formwork):
Since shell stone masonry is characterized by an uneven surface, it is impossible to lay the slabs exactly over the masonry. Often a level difference of 5-15 mm is formed between the plates. Considering this, in order for the ceiling from the floor panels to turn out to be even, it is possible to make a leveling concrete belt, on which the slabs will then be laid. However, this measure will only help if the plates themselves are perfectly flat. Experienced builders note that the surface of factory reinforced concrete slabs is often uneven, which excludes the possibility of making a flat ceiling without further finishing.
INTERIOR DECORATION OF THE HOUSE WALLS FROM SHELLS
The best option for finishing is plaster, since it adheres perfectly to the shell rock, due to its porous rough surface. Professional builders do not recommend decorating shell walls with plasterboard on a galvanized profile or wooden beam, since it is very difficult to drill this stone to install the profile. Due to the heterogeneous structure of the shell rock, the drill is strongly displaced from its initial position during drilling.
It is believed that when plastering shell rock, you must first fix a steel mesh on it, but this is not the case - a layer of plaster will fix well on the stone without using a mesh. The main thing is to spray it before applying the base coat to create the initial rough coat.
In humid rooms, only cement-sand plaster is used, and for drier rooms, you can take gypsum. Before calculating the cost-effectiveness of choosing between gypsum and cement-sand plaster, it is necessary to take into account the thickness of the future plaster layer.
If the thickness of the plaster is small (up to 2 cm), it is more advantageous to use gypsum machine plaster. If the layer thickness reaches 3-4 cm (or more), then the cost of gypsum plaster will outweigh the benefit from cheaper work in comparison with ordinary cement-sand plaster, which is applied by hand.
If your choice fell on machine gypsum plaster, do not forget that such material will be beneficial only for large volumes of work - 200 sq. meters of walls or more. It should also be remembered that most of the models of installations for plastering walls work only from a three-phase voltage network.
The surface of natural shell rock is beautiful in its own way - it has an interesting texture and a pleasant warm color. Therefore, an open cladding with this stone can be used as a decoration. Especially organically, the shell rock finish will fit into the interior, where there are elements made of wood or other natural materials.
Strength and weight
The opinion that the strength of shell rock is not enough for building a house , became quite widespread due to the ease of processing this stone. It is also worth mentioning the relatively low specific gravity (about one and a half times less than that of ceramic bricks).
It is quite understandable that a large and not very heavy block does not inspire confidence. It seems that the stone will not withstand significant stress and pressure.
Meanwhile, according to the conclusion of the Kharkiv Institute of Forensic Expertise. Bocarius, even with a minimum density, the shell rock has a sufficient margin of safety. According to this indicator, there are three groups of construction shell rock - M-15, M-25 and M-35.
A higher grade means a smaller pore size and increased material density.
Coquina stamps
Shell rock stamps M-15(there are also M-10 and M-20) differs in relatively low strength and high porosity. When thrown on a hard surface, it will split into several parts, and during unloading it can crumble and acquire an uneven surface.
Therefore, such a stone can be used for the construction of outbuildings, fences and partitions.
Products of the M-35 brand are characterized by high mechanical strength and low porosity. True, the increased weight is about 20-25 kg. When dropped, quality shell rock brand M-35 remains intact.
Such a stone used for the construction of load-bearing walls of buildings and basements, arrangement of foundations and cellars... In a two-story house, structures of the first floor are often made from it.
The characteristics of stones of the M-25 brand are considered optimal: sufficient strength, density and porosity. From shell rock M-25, load-bearing walls of houses are erected in one or two floors, non-load-bearing walls and partitions... In addition, it is used in the southern regions to fill the frame of multi-storey buildings. One such stone should weigh about 14-17 kg.
The resistance and endurance of the material is influenced by the content of the natural binder - lime. This figure must be at least 25%.
The proportion of silicon oxide (or simply sand) sometimes reaches 40%, but ideally is no more than 15%. In good stones, the sum of these two components is in the range of 30-40%, otherwise the blocks will be characterized by increased fragility and flowability.
At the same time, too little lime and sand means increased porosity of the shell rock, and this will reduce its thermal performance and moisture resistance, and reduce its service life. .jpg)
However, you need to understand that the strength (grade) of the "shell" is lower than that of a ceramic brick or aerated block. It is undesirable to erect walls above 6-7 m from it, and when building the second (non-mansard) floor, it is necessary to perform a reinforced belt.
Fragility of a stone
Impact resistance of these stones leaves much to be desired, therefore be sure to be careful when handling shell rock, both upon delivery and at the construction site.
In order for the shell blocks to arrive at the place of construction of the house intact, they should be transported on trucks with flat bodies, in pallets fastened with tapes or cables.
Throwing blocks while unloading is not even worth it. If this work is performed by a hired team of builders, it is better for the owner of the house to be present when loading and unloading the material. Then it will be possible to check the quality of the goods and control their storage.
There is another important point - if you want to fix on the wall inside the house, not a picture or a photograph, but something more significant (for example, a rack or kitchen cabinet), you will need special chemical dowels. Simple ones can gradually fall out, especially if they fall into cavities.
On the other hand, the comparative fragility of the shell rock becomes an advantage during natural disasters. Of course, Ukraine is not Japan, where earthquakes of different strengths occur every day.
However, it must be remembered that some regions of our country (Carpathians, Crimea, Odessa region) are in high-risk zones. A building made of shell rock is quite resistant to "shaking", but if it collapses in the event of a strong earthquake, then shell blocks will disintegrate into small parts and cause much less damage than brick or, especially, concrete.