The construction industry today uses a wide range of materials, many of which are made possible by advances in technology and chemical industry. At the same time, of no less interest are those building materials that have been known to us for a long time and have been used for centuries. Brick comes to mind first, but shell rock also falls into this category.
As the name suggests, this material is created from the shells of sea creatures. In ancient times, shells accumulated on the seabed, compressed together with sand and limestone. At the same time, those regions that were previously covered with water eventually became dry land, exposing large deposits of this material for free mining. At the moment, such deposits in the post-Soviet space are located in Crimea, Azerbaijan, Kyrgyzstan, Dagestan and other regions.
Received naturally the material is widely used in construction. As a rule, blocks and plates are used in this direction, which are cut from solid shell rock masses, similar to what happens with marble.
The material has several types, determined by etiology and composition, held together by lime. For example, oolitic shell rock resembles fish eggs - being tightly bound together spherical minerals. As for pisolite, in this case we're talking about about fragments the size of a pea, also tightly combined with each other and having particles of mollusk shells in their centers. Finally, the material is travertine, which is formed by sedimentary calcite. If there is a porous structure, such travertine is called calcareous tuff.
As for brands, there are several of them: M15, M25, M35. As with concrete, the higher the number, the higher the strength of the material. And if M15 can only be used for construction internal partitions, then M35 is quite suitable for building walls in private and even multi-story structures. The strength of the latter allows it to be used even in the construction of foundation structures (basements and ground floors).
Important! Shell rock is not only safe, but also good for health. In rooms built from it or lined with it, there is an increased concentration of beneficial iodine ions. The bactericidal properties of the material are also known.
It is worth noting that most of the disadvantages of shell rock are quite easy to work around. Thus, insufficient strength compared to concrete in the construction of multi-story structures is solved by creating reinforcement joints under the floor slabs. However, here it should still be remembered that concrete (in its classic, not lightweight version) still surpasses shell rock in load-bearing qualities, and therefore if this parameter is extremely important (as happens in the construction of the foundation of heavy houses), then it is better to give preference exactly to him.
Some write down the disadvantages that the material is difficult to transport and store, as it can easily crack. Be more careful and this will no longer be a problem.
The porous structure of shell rock means that the material absorbs a lot of moisture. And this could really be the number one problem. Therefore, storing it in damp places is not recommended, nor is working in humid weather. Finally, to protect against moisture, the walls will need additional finishing. In this sense this natural material very similar to lightweight concrete.
Important! Now, in order for shell rock to acquire excellent hydrophobic qualities, it is enough to coat it with a special impregnation.
Important! One of the properties of the material is its great heterogeneity. Depending on the quarry, the structure may be different, as well as the load-bearing properties. It is possible that the materials may even contain hidden voids, which significantly reduce the quality. Therefore, it is recommended to take shell rock from one quarry and from one batch.
Experts advise choosing shell rock with a small amount pores and a fairly dense structure. In this case, the weight of the block should not be less than 16 kilograms, since if this indicator is not achieved, this may indicate the presence of voids inside. You can also check the quality by hitting it against hard surface. If the stone is grade M35, then it will not break at all. Well, in general, the fewer pieces the shell rock fell into, the denser and better quality the specimen you got.
As mentioned above, shell rock can be used in wide range directions. Wide Application he got in finishing works due to its unique and extremely impressive texture with the presence of shells. The material palette is mainly represented by soft pastel shades, the number of which is very large, which opens up rich design possibilities in the use of stone.
As for the walls, during construction their thickness is usually 40 centimeters. In case of climatic conditions in many regions of Russia, additional insulation is not required for such walls. But if your winters are still harsh and long, then covering the wall with insulation will help reduce heating costs. When creating a monolithic concrete seismic belt, a wall made of shell rock can withstand floors made of any material.
Shell rock itself can also serve as a kind of “fur coat” for insulating walls made of other materials. But at the same time, the main walls must be strong, capable of withstanding such insulation, for example, brick.
Finally, designers will certainly like the material when creating columns, as well as small architectural forms on a personal plot.
The Crimean shell rock, also known to us by its nickname limestone shell rock, as well as zheltyak, cap, meotis, sandstone, is scientific confirmation of this. The properties of shell rock are distinguished by their uniqueness.
Main advantages Crimean Shell Rock:
– low thermal conductivity of the shell;
– high density of shell rock pressed in the ground;
– shell rock is easy to process;
– medicinal properties iodine which contains small shell rock;
– radiation-inert qualities, shell rock does not transmit radiation;
– excellent level of sound insulation of shell tiles;
– excellent level of absorption harmful substances;
– low price shell rock;
– environmental friendliness of the material.
The main difference between this wall material, like shell rock, is that it is used in the creation of various architectural structures. Shell rock is traditionally used for building houses, garages, etc. The stone is easy to process and does not enter into chemical reaction with other building cladding materials. Another very important positive feature The advantage of shell rock is that it does not require any procedure for leveling its surface - shell rock has a porous structure and is automatically leveled using a fastening mortar.
Properties of shell rock:
Low background radiation. All substances located on the surface of our planet have a natural background radiation. For example, in Lugansk the average is 19 micrograms/hour (the norm permissible in Ukraine is 25 micrograms/hour.) The natural radiation background of shell rock is 13 micrograms/hour. Based on the above facts, it can be argued that the background of shell rock is at least neutral.
Low thermal conductivity. The thermal conductivity coefficient of shell rock varies in the range from 0.2 to 0.35 kcal.m.hour.Os. This is due to the presence air gaps Inside the shell rock, the blocks made from it have very low thermal conductivity. The thermal conductivity of a shell rock wall is two or even three times lower regular wall made of concrete.
Noise insulation. The natural porosity of the material is 40-70% and this gives its results. Shell rock has a developed capillary system filled with air in its microstructure. Thanks to this characteristic, the shell has good noise-reducing properties.
Frost resistance. The resistance of shell rock to frost can reach 50-70 cycles. The compressive strength of the stone in an air-dry state is 105 kg/cm, in a moisture-saturated state it is 74 kg/cm. The surface of the shell rock “breathes” freely. With the help of the porous structure, excess moisture is forced out, without the stone itself being destroyed. That is why a house made of shell rock will always be dry and comfortable.
Inertia. Shell does not react with substances contained in other building materials.
Chemical properties. Shell is a natural filter. It contains iodine and salt, substances characterized by antibactericidal properties. People who are in such an atmosphere improve their mood, their vitality rises, and the general condition of the body is strengthened.
To summarize all that has been said, we can say with confidence that shell rock is a durable and at the same time lightweight building material. This material is characterized by excellent thermal insulation properties. Shell rock prevents the penetration of radiation and is an excellent soundproofing material. Another indisputable advantage of this stone is that it contains a large amount of iodine, which makes this building material not only of high quality, but also beneficial for the body. Shell rock has a unique natural texture and color; it is quite resistant to environmental influences.
This material is relatively cheap, which is a big plus in the construction of houses. IN Lately many structures began to be built from shell rock. They even build multi-storey cottages from it.
For many generations people have been building their houses from shell rock. The fact that this natural stone has stood the test of time is why it has proven so popular. Recently, shell rock has been increasingly used not only in private construction, but also in industry.
The basis of shell rock is calcareous rocks. Based on the origin and structure of limestone, shell rock is divided into a large number of varieties.
It happens that some types of limestone are cemented into cells and are formed from shell particles.
Limestone consisting of small spherical minerals, the size of fish eggs, bound together is called oolite. Pisolite is a limestone consisting of spherical minerals already the size of a pea, but with a core, a grain of sand or a fragment of a shell.
If limestone was formed from calcite sediments from a saturated source carbon dioxide, this is travertine. With a porous structure, such limestone is called calcareous tuff.
Shell rock is a type of limestone rock, usually white or milky in color. As already mentioned, it is widely used in construction. Thanks to its structure it is very easy to process. If desired, you can cut the shell rock to any size.
The only limitation is that shell rock large sizes inconvenient to transport and use in construction.
Due to its porosity, shell rock has good sound and heat insulation properties. If you look closely at a cut of a stone, you can see representatives of flora and fauna, for example, well-preserved shells of mollusks that existed millions of years ago. So, along with the building material, you hold in your hands real story Cretaceous period. Shell rock is used for housing construction mainly due to the properties mentioned above, excellent sound and heat insulation, which are explained by its increased porosity. At the same time, it can very well accumulate and transmit solar heat, thanks to which excellent living conditions are created indoors.
In addition, many more can be added to these main advantages. beneficial properties. Wall blocks made from shell rock have a relatively low mass, which makes it easy to transport and use in construction, the material is heat-resistant, frost-resistant, and can be built in cold climates. As already mentioned, it is easy to process, you can get blocks of almost any size.
There is another attractive factor, it is not only environmental friendliness, but also beneficial influence on the human body. This is due to the high salt and iodine content in shellfish.
Another advantage of easily processed shell rock is that because of this quality it remains one of the best facing materials for price-quality. Having built a house from shell rock, you will forget what dampness, fungus and mold on the walls are.
Shell rock has numerous pores and passages that contain air. As you and I know from the physics course, air is a poor conductor of heat and sound, which is what we need. Thanks to these qualities, heating and heat retention in a shell rock house does not require large energy costs. It turns out that a house made of shell rock also saves us fuel.
Shell rock, in comparison with other masonry materials, began to be used in the construction of houses much faster than all modern building materials, since extracting shell rock is much easier than producing any modern material. As we know, shell rock consists of shells of smallmouths, either broken into pieces or whole. Shell rock has a porous structure, that is, air layers, due to which heat is retained. Geographically, shell rock can be found in Neogene deposits of the southern part of our country - on the Crimean Peninsula and Odessa region, Azerbaijan, and so on. It is also mined in countries such as Romania and Poland.
Shell rock (shell rock, shell limestone, shell) is a stone that belongs to the class of natural masonry building materials. This material is extracted from solid deposits of limestone by mechanical sawing in places where there are natural deposits of this material, in particular in the Crimea. Formed by pressing mollusk shells, sand, lime and other natural elements, it has a low volumetric weight. In terms of its composition, shell rock has a porous microstructure that is filled with air. Thanks to this feature, shell rock has unique heat and sound insulation.
Shell shell is used in the construction of house walls. The use of shell rock significantly saves money on the purchase of insulation, fire-resistant and noise-reducing materials.
Shell is considered one of the most environmentally friendly building materials. Unique chemical composition This material has a beneficial effect on the human body. Content sea salts, highlighting in environment Iodine, which is so beneficial for the human body, protects against many diseases of the respiratory tract and heart. The air in a house built from shell rock is cool in summer and warm in winter. There are no rodents living in this house.
Absolutely inert material. Shell rock does not react with substances contained in other building materials.
Shell shell is considered the only material in the world that has protective properties against radiation.
The technical characteristics of shell rock allow it to be used in the construction of a wide variety of architectural structures. Due to its porous structure, it acts as a natural filter. The porous structure of the stone, like a sponge, absorbs all substances harmful to humans, thereby preventing them from entering the house.
The thermal conductivity of a wall made of shell rock is two to three times lower than that of a conventional wall made of concrete, because... Due to the air layers inside the stone, it has a low density and very low thermal conductivity. It is thanks to this characteristic that shell rock has excellent noise-reducing properties. Shell rock is the best wall material for the construction of houses using technology permanent formwork. Those. in addition to the wall frame, with correct processing stone, you get additional cladding on both sides.
Now a little in numbers:
Thermal conductivity of stone 0.3-0.8 W/(M.K)
Average density (volumetric mass) up to 2100 kg/cub.m.
Porosity 30-60%
Dimensions 380x180x180 mm.
Moisture absorption 17 -20%
Frost resistance 25 cycles.
Crimean shell rock is a unique building material of natural origin. This stone belongs to the limestone family. It is mined in quarries and cut into blocks.
Shell rock is excellent for construction individual houses and buildings, and for “filling” walls in multi-story buildings. Today it is the most popular building material in Crimea.
Shell stone is not very heavy and is characterized by a fairly high density(depending on the brand of stone).
Thanks to its rectangular shape excellent for masonry.
Main characteristics of shell rock:
As can be seen from the above characteristics, shell stone is excellent for construction.
There are several brands of shell rock depending on its density:
Particularly popular is shell rock M-25., because its characteristics allow it to be used for almost any type of construction.
In quarries, stone is sawed into blocks standard sizes: 180mm*180mm*380mm. This size is provided for by GOSTs of the Russian Federation.
“In practice” the stone may deviate in length, but not more than 1 cm. Deviations in width and height are not allowed (standard 180mm).
It is best to order stone from quarries. Thus, you can buy Crimean shell rock directly from the manufacturer with delivery to your facility.
Contact our company and we will bring you a custom-made stone. The minimum quantity for delivery is 1000 blocks. Delivery takes 2-4 days after ordering (depending on the workload of the quarry and the availability of free vehicles for transportation).
We are starting a series of articles about materials for masonry walls. By and large, we will consider facts from the forefront of construction and operation; most of the practical considerations will be focused on the nuances of each material that should be taken into account to obtain the expected quality result. Beautiful marketing articles are the lot of those interested in selling, but we have the whole inside out for a better understanding of the material.
Now let's talk about shell rock (shell rock, limestone).
Rakushnyak — rock, which refers to pure limestones.
Absolutely natural and environmentally friendly pure material, which, in fact, won the preference of many. I myself have a very respectful attitude towards this material, nature, after all.
For the construction of a private house, shell rock has a number of positive properties– previously mentioned environmental friendliness, vapor permeability, excellent sound insulation, high thermal inertia, high degree of adhesion with masonry and plaster mortars.
Natural radioactivity high-quality shell rock, according to various sources, is at the level of 13 microR/hour (on sales sites it is clearly underestimated to 6-9 microR/hour), for comparison, the background radiation in Kyiv as of the beginning of 2015 is 15.4 microR/hour.
what sellers are silent about
The websites of companies specializing in the sale of shell rock also indicate such advantages as high thermal insulation qualities, cost-effectiveness of masonry up to 50% compared to brick, and faster completion times for masonry work. These benefits in practice construction site and later, during operation, they do not show themselves, which means they are stretched to increase purchasing attractiveness, nothing more.
In addition, the features of the material that are usually kept silent include a high degree of water absorption, depending on the density, a high percentage of open porosity or increased “holeiness”, often heterogeneity of the stone structure, variation in density, low predictability of the quality of the material delivered from the quarry, and inaccurate geometry.
About positive sides A lot of material has been written, but remember its main advantage - its natural environmental friendliness. But this remains an advantage only if interior decoration premises completed environmentally friendly materials. Finishing with store-bought plasters or drywall (these materials contain a large number of compounds harmful to humans) largely eliminates the environmental friendliness of shell rock for the residents of the house.
high water absorption!
Water absorption of shell rock. Being, in fact, limestone, shell rock is very greedy for water - its water absorption is on average 3-4 times higher in comparison with red brick, i.e. the amount of condensed moisture balanced in the material during operation will be 3-4 times greater under the same conditions. Steam, after condensation and transition to the state of water in the material, replaces air, displacing it from micropores, which leads to an increase in the thermal conductivity of shell rock walls.
Worth knowing:
That is why shell rock cannot be used in rooms with high humidity, below the zero mark and for laying the plinth.
That is why shell rock must be thermally insulated during construction, and it is especially correct to do this with a layer of thermal insulation that will bring the dew point from the load-bearing shell rock structures into the plane of the insulation. There will be a separate topic about this in detail.
That is why thermal insulation must be done exclusively with vapor-permeable insulation, which will not prevent moisture from escaping from the structure of the external walls. These include basalt, light adobe, reed, perlite, vermiculite, and light sawdust concrete. In no case should the insulation of shell rock be foam glass and expanded polystyrene, both ordinary and extruded.
porosity and perforation of shell rock
High percentage of open porosity and holeiness negatively affect the thermal insulation qualities of shell rock. A number of stones have through holes visible in the light. Heat passes through such stones not only due to thermal conductivity, but also due to air infiltration, essentially micro-drafts, which carry heat away from the house with a bang.
There are many pores (both open and closed) in stones of lower density and, accordingly, grade, usually M10-15. It cannot be used for structural masonry, only for insulation, decorative works or in broken form as a filler in screeds.
Denser shell rocks, which are more compressed, have fewer pores. The layers accumulate into a denser layer - limestone takes the place of pores - density increases - the number of micropores important for thermal insulation decreases - the grade of stone increases - increases load bearing capacity- Thermal insulation capacity decreases. Such stones, as a rule, belong to the M25 density.
Large, evenly distributed holes, similar to holes in cheese, in such stones are no longer pores, but voids through which heat transfer occurs due to convection, and not heat transfer, as in the case of pores. With convection, heat transfer occurs faster.
There are also through cracks (not pores) in stones of varying densities. These are stones of uneven structure; the difference in densities in the form of different layers is clearly visible on them. The transition zone is always very weak, usually in the form of a gap with rare bridges, the bearing capacity of the entire stone (at the weakest link) is low. Air through such cracks can penetrate to the warm surfaces of the wall due to infiltration.
Open pores, holes and cracks significantly reduce the thermal insulation qualities of shell rock. We have already talked about discomfort from cold walls earlier in this article.
plastering walls
Worth knowing:
That is why you cannot decorate the inside of a shell with wood or plasterboard without first rough plastering the walls.
That is why, for the same reason, it is also worthwhile to carry out rough plastering before external insulation.
That is why in houses made of shell rock, outlets are often siphoned off with cold air if the outlet sockets are not first plastered.
That is why before installing windows and doors internal slopes openings, including the mounting plane, should be sanded off.
Plastering in all of the above cases will cover all cracks and holes, reduce the negative impact of infiltration, and additionally create an additional heat-inertial layer on the warm side.
That is why in most cases the thermal conductivity coefficient, which is announced on specialized sites, is very underestimated. The material is exhibited with best side, according to the ideal stone. In reality, the thermal conductivity of shell and solid brick masonry is almost the same. If you have the opportunity, talk to the owners of uninsulated houses. Better yet, look at the readings yourself. gas meter, because in most cases, owners try to embellish the advantages of their home and keep silent about the shortcomings. This is already the psychology of property.
Relatively high thermal inertia . Regarding wood, foamed concrete and frame system- higher, relative to brick or adobe - the same or slightly lower, but in general, shell rock can confidently be classified as a material with high thermal inertia. Whether this is good or not depends on the format of use at home.
home for permanent residence
For a house intended for permanent residence, this characteristic is definitely good. Thermal inertia of shell rock creates the effect of a heat accumulator and emitter radiant heat during the heating season and coolness on hot summer days.
For country house without constant maintenance temperature regime This quality, on the contrary, is disadvantageous. Arriving in winter to cold shell rock walls that have become damp with moisture, warming them up will be a costly and time-consuming undertaking, and staying in such a house will be extremely uncomfortable and a real test of hardening for the whole family.
Shell rock is a material for a house in which you will live permanently.
At the same time, do not under any circumstances decorate the walls with plasterboard, this is fundamentally wrong. In addition to deteriorating the best advantage of shell rock (environmental friendliness), you also lose thermal inertia, move the dew point closer to the warm internal space, which means you increase moisture accumulation in the walls and create improved conditions for the life of fungi and bacteria, and to top it off, you create ideal conditions for rodents to live in. right between the shell rock and the drywall.
Shell stone finishing is a natural plaster based on clay, lime and sand with a small addition of fiber, gypsum/cement. Details about natural plasters We'll definitely talk separately.
This concludes the first part of the discussion of shell rock. The continuation of the article is already ready and is
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