Do-it-yourself sewerage from concrete rings. Do-it-yourself sewerage in the country from concrete rings
Disposal of household waste into cesspools can lead to sad consequences: you risk poisoning garden crops and eroding the soil. Therefore, it will be difficult to do without autonomous sewerage in a modern dacha.Charting
The device of a septic tank depends on the number of residents and the attendance of the cottage. For a home that has washing machine, shower and washbasin, a standard design consisting of two cleaning chambers will do. For a small family with a minimum set of household appliances, one concrete ring per 0.62 m³ is enough.
We build sewerage in the country
The calculation formula for a certain number of people living in the country is as follows. Let's say 5 people live in the house (age can be ignored). Each family member uses on average about 50 liters of water, therefore, the daily consumption is 250 liters. 1 well out of 3 concrete rings can hold no more than 3 thousand liters. This means that for 5 people the daily consumption is 0.25 m³. That is, 3 wells (3 rings each) freely serve a family of 5 people for a month.
Note that the calculation example was made for a concrete ring of average size 0.62 m³.
Let's move on to drawing up a sewerage plan. The placement guidelines include the following:
- The treatment plant should not be located near a residential building closer than 5 m;
- The filtration device should not be placed further than 20 meters from the dwelling (otherwise there are problems with the pipeline);
- Sewerage should not be located near sources of drinking water in the country closer than 50 m;
- There should be an entrance for special equipment.
Calculation of the cost of hiring equipment and purchasing materials
Digging a pit by hand is long and difficult, so it is recommended to hire special equipment - an excavator, a bulldozer for cleaning soil and a dump truck for removing excess land. You will also need a crane to install concrete rings.
How much does it cost to call a technician? The average price of digging a pit and removing land does not exceed 350 rubles per 1 m³. Calculate the cost of arranging 3 pits. The volume of each pit is 1.5 m³, which means that you will need approximately 1,600 rubles for earthworks.
The average cost of 1 concrete ring with a volume of 0.6 m³ is 4.5 thousand rubles. To build a well of 3 rings, you will need 13.5 thousand rubles.
Cost of additional materials:
- 2 bags of cement (150–200 rubles);
- 100 kg of sand (120 rubles sand + 200–500 rubles delivery);
In total, a complete sewage system in the country for 5 people will cost you 43 thousand rubles.
Pit preparation
After the departure of the equipment, you need to trim the sharp corners and give the pit a rounded shape. Remember: you need to strive to ensure that the diameter of the pit is at least 2.5 m. Clear the well pit from the ground and start preparing for the next step - creating a pillow of sand, gravel and rubble.
The foundation plays an important role in waterproofing - its proper construction prevents waste from being absorbed into the ground and spoiling groundwater or garden crops. If you have the finances, you can make high-quality waterproofing of the rings by filling the bottom with concrete.
Installation of concrete rings
Rings are installed only with a crane. Renting a lift will cost you no more than 700 rubles for a few hours of work. Rings are sequentially installed on top of each other. After installation, the rings are fastened with metal plates for reliability.
Drilling concrete rings is best done with a powerful hammer drill and special drills. Drill two holes - one above and one below the joint, then put a metal plate on them and attach it with bolts on nuts, tightening them with an adjustable wrench.
Next, the sewer is sealed. In construction practice, it is customary to use concrete or "Aquabarrier" - waterproof plaster. You can make your own concrete. It is prepared in a ratio of 2:1 (2 buckets of sand and 1 cement). The ingredients are thoroughly mixed and poured with a small amount of water. Add water until the mixture resembles melted butter. Concrete is applied along the internal and external joints of the well.
Drainage system device
Step-by-step instruction:
Pipe installation and seam sealing
At the last stage, you need to punch through the concrete rings with a perforator. You can make a hole of the required size only with the help of professional drills (Bosh, Makita, Metabo) and a powerful puncher. Drilling a hole is recommended at the very bottom of the well.
A plastic pipe is inserted into the well by 10–15 cm, no more. Separate wells are connected using plastic pipes. A drain hole for another well must be made on a hill, not reaching 20-30 cm to the very top of the rings.
While the sealed seams dry, you can start digging a trench leading from a private house to a well.
Video: Simple sewerage in a site with a high level of groundwater
It is no secret that one of the most difficult stages in the construction of a modern private house is sewage equipment. There are many proposals for arranging such a system on the building materials market. Let's dwell on the most affordable option in terms of cost and complexity - do-it-yourself sewerage from concrete rings.
Advantages and disadvantages
Let's define the strengths and weaknesses of the sewerage device from concrete rings.
Advantages:
- Fast installation and easy sealing of joints.
- The combination of metal reinforcement with concrete is much stronger than brickwork.
- The service life of rings is much longer than many other materials.
- Initially, the correct round shape of the structure, which is extremely difficult to repeat when laying bricks.
- Convenience of carrying out isolation from external moisture.
Flaws:
- An impressive amount of detail. You have to use technology.
- Manual movement of the rings over the territory is excluded to prevent cracking from their rolling.
A site that does not have permanent residents does not require the equipment of a complex sewerage system. For a small amount of drains, a cesspool will be enough.
By the way: in contrast to the constant height of 0.9 m, reinforced concrete rings are produced in different widths. Most often, rings from 0.7 m to 2 m are used for sewerage of a private house, based on the intensity of filling. The average indicator among the various options is the installation of 3-4 rings one meter in diameter.
Necessary materials:
- Three rings 1x0.9 m.
- The usual mixture of sand and cement for pouring the bottom of the pit and sealing the junctions of adjacent rings and the cover.
- Blanks for equipment of a not too massive foundation for rings, no more than two bricks.
- Cover made of concrete, equipped with a hatch.
First of all, a foundation pit is prepared, taking into account the radius tolerance to speed up the laying. The base is poured along the contour of the concrete rings and the bottom of the pit.
After sufficient drying of the bottom (from 3 to 5 days), rings are installed. Since the laying of the rings is possible only with the presence of construction equipment, it is necessary to provide in advance free passage and a place for placing the equipment.
Once again about the need for tolerances in the dimensions of the pit. If the markup is incorrect, the overrun of the equipment rental time will lead to an increase in costs.
Upon completion of the installation of the rings, the inner surface is sealed by applying plaster. This prevents untreated effluents from entering the ground. Then a pipe is laid from the building, a concrete cover is mounted, a ventilation pipe 0.4-0.6 m high is installed.
The pit can be put into operation. Now you need to clean it every 6 months using the services of municipal equipment.
Thus, we figured out. The process is quite laborious, but simple.
The next issue will be the equipment of a more modern, independent drainage system for a summer cottage.
For a country house where the family lives permanently, using water in full, it is necessary to equip a sewerage system, supplemented by a septic tank and a filtration well.
Visually, such a system looks like this (see Fig.)
The element layout is as follows:
It is necessary to prepare:
- Three rings 1x0.9 m.
- Cement-sand mixture for concreting the bottom of the pit and the joints of adjacent rings and the cover.
- Material for pouring the foundation for the rings.
- Sand in the amount necessary for pouring 0.5 m of the pillow.
- Gravel in the amount necessary to create a 0.2 m layer between the sand layer and the well; 0.2 m of external sprinkling from the bottom level with a height of 0.9 m.
- Cover made of concrete with a place for a hatch.
The functional load on the well for filtration is to divert treated effluents directly into the ground.
Wastewater through the sewer pipe from the building passes into a septic tank, equipped according to the scheme of the drain pit. In its volume, the separation of insoluble components occurs. The septic tank is carried out with mandatory isolation from the premature release of liquid into the soil, ranging in size from 3 to 4 cubic meters per 4 living people with an average amount of water use of 150 liters per day for each.
If there is a sewer riser in the building, the septic tank is ventilated through it and the installation of an additional pipe is optional. The dimensions of the sewer pipe must comply with the accepted standard, at least 10 cm in diameter. The digging depth is about 120 cm.
The minimum slope of the sewer for the passage of liquid waste through the pipe is 20 mm, the maximum is 50 mm for every 100 cm of the pipe, which makes it necessary to foresee the depth of digging in sewer wells in advance.
According to the requirements of SNIP, a septic tank can be located at a distance of at least 5-20 m from the dwelling and 20 m from the place of water intake in the presence of soil with a predominance of clay, and 50 m in soil with a high sand content.
The transition from the septic tank to the well for filtration is equipped below the point where the pipe enters the septic tank from the building by 50-150 mm.
Installation of a well for filtration
The pit for the well for filtration must be deepened to the sandy layer. If not possible, a drainage field is placed.
Work sequence:
- A sand cushion of 0.5 m is poured and rammed.
- Gravel 0.2 m is located on top.
- The bottom ring with drainage holes is being prepared for installation.
- The ring is installed by a crane on a prepared place.
- The following rings are mounted, interconnected. It is not necessary to seal the joints.
- The outer side of the rings is covered with gravel to the height of the drainage holes to protect them from overlapping with soil.
- An overflow pipe is installed from the septic tank to the well.
- From above, the entire system is covered with a concrete lid and a layer of earth.
The result is the following construction:
After the work, liquid waste, flowing from the dwelling to, leaves an insoluble sediment in it, the purified water enters the drainage well, where it is absorbed into the soil. The difference between the levels of the bottom of the well and the nearest aquifer should be more than a meter.
By the way: manholes in sewerage wells should be protected as much as possible from accidental falling of people there.
The construction of a country house is best to start with the arrangement of sewers. Agree, it is not an easy task to properly design and organize wastewater disposal at the site. We'll have to think carefully about solving this problem. After all, improper arrangement of sewerage threatens to make life in the house unbearable.
We will tell you how to independently create a functional septic tank on the site. So, among affordable materials used in the construction of local treatment facilities, today the most popular are concrete rings.
It will be about how to build septic tanks from rings with your own hands, and what to consider during the installation process. In addition, in the article you will find videos with advice from experienced professionals, detailed instructions for installing a septic tank, as well as many useful recommendations about the sewerage system in a country house.
Concrete rings, which are the basis for the manufacture of structure walls, have high operational parameters.
Thanks to their technical advantages, the tanks built from them are durable and highly resistant to aggressive media.
Concrete ring septic tanks, designed for collection and subsequent biological treatment of wastewater - ideal for well-drained and, moreover, soils not prone to frost heaving
The arrangement of such systems requires large squares of space. But under given conditions, sometimes only such a system works.
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Polypropylene pipes are famous for their strength and elasticity; their operating temperature is about 65°C
The diameter of asbestos-cement or polymer pipes used for overflow should be 110-120 mm.
Step # 3 - digging a pit and arranging the bottom
Earthwork is best done after the onset of the first frost or in the hottest months. During this period, the lowest level of groundwater is observed.
The pit can be dug manually by hiring a team of "diggers" for this, or using the services of an excavator. If we take into account the costs of excavation, then the costs for a team of diggers will be comparable to the amounts that will be spent on calling special equipment.
The dimensions of the finished pit should exceed the dimensions of the installed rings by 50-80 cm. This will simplify the installation process and allow external waterproofing of the construction joints.
When calculating the depth of the pit, three values \u200b\u200bare summed up: the height of a monolithic or filtration cushion (20-30 cm) + the height of the rings (indicated in the table) + the height of the slab (15 cm).
A large amount of soil extracted from the pit should be removed from the site immediately, using the same machine that delivered the rings.
The pit for the installation of a treatment plant should be two-tiered: its second tank should be buried 50 cm lower than the first. Alternatively, dig your own hole for each tank.
To bring sewer pipes, trenches are dug, laying them below the freezing depth of the soil. The width and depth of the trenches are selected based on the dimensions of the rings used to build the tanks. Most often they are made 50 cm wide with a depth of 1.2-1.5 m.
The simplest and most common option for assembly in a private house is a sewer from concrete rings. The device of a well from 1-3 elements assembled from special standard concrete components.
This concept, among other things, implies the use of the amenities provided by the connection of housing to the main engineering networks of the utility infrastructure. Not always in the area of \u200b\u200bresidence there are central communications for water supply and disposal of household wastewater. Therefore, conveniences, in the form of an autonomous sewage system, have to be created independently.
All property owners want to make permanent residence in a private house and seasonal stay at their favorite dacha comfortable. Consider what a sewerage from concrete septic tanks is
Benefits of concrete
A septic tank for receiving household waste can be made of brick, polymeric materials, stone, metal, concrete. The resulting structure is not too loaded, its durability is affected by the resistance of the source material to aggressive substances, constant humidity. The construction of the walls of the sewer well from concrete rings is considered ideal for the following reasons:
- Concrete elements are used in the construction of a septic tank on various soils, their resistance to compressive deformations allows them to withstand pressure from the displacement of soil layers and groundwater.
- Material availability.
- High speed sewer construction using concrete products.
- Sewerage from concrete rings is durable and easy to maintain.
- Rings allow you to make a device of the desired depth and diameter.
- The resistance of the material to aggressive substances, the composition of groundwater and temperature extremes.
- Ease of self-assembly.
- Large selection of waterproofing materials to protect the walls of the future well.
- Thanks to the metal reinforcement elements, concrete products are highly durable.
- Factory-made products are designed for tight docking.
The main disadvantages during work: weight, certain difficulties with delivery and loading operations, the possible need for the use of lifting equipment and additional labor.
Types and types of concrete components
There are two types - wall and additional.
Wall finished products in the form of a ring can have the following dimensions: inner diameter - 0.7-2.0 m; wall thickness - 70-100 mm; standard height - 890 mm. With their help, the necks of any wells are erected. For sewerage in a private house, erected from concrete rings with their own hands, products with an internal diameter 1.5 m.
Additional products differ from wall non-standard height. With their help, the required depth is adjusted when it is not a multiple of the height of standard rings.
The following types of rings are used in the work:
- having a blind bottom. Needed for overflow sewers, whose settling wells accumulate silt at the bottom (periodically removed by special equipment).
- without lock. Ordinary straight rings, for the connection of which a cement mortar is used.
- with lock connection. This view is distinguished by notches on one side and protrusions on the other. Installation of products consists in fitting and fixing with the help of the protrusions getting into the recesses. Such a lock will prevent the elements from moving during the operation of the sewer well.
- Filtration. Walls with a uniform arrangement of holes allow the liquid to go into the ground. These rings are intended for the construction of filtration wells.
Stages of installation of a well for sewerage
Consider how to make a sewer in a private house with your own hands from concrete rings. And if a decision is made to entrust the execution of work to a specialized organization, then the information received will help to carry out quality control over the installation progress and facilitate communication with employees.
Location selection
The location of the sewer septic tank is selected taking into account certain norms and requirements. It should be no closer than: 5 m - from the boundaries of the estate; 5-10 m - from a residential building (so as not to wash the foundation); 30 m - from the shore of the nearest reservoir; 20 m (50 m) - from the water intake on clay (sandy) soil; 3 m - from trails, roads, trees, shrubs, vegetable gardens. The bottom of the well should always be above the groundwater level in the area. To the chosen place, an entrance should be provided or later laid for periodic pumping of silty masses by special equipment.
Calculations and scheme of a septic tank
To install a sewerage system in a private house with your own hands from concrete rings, you will need a construction scheme drawn up according to preliminary calculations of the volume of water consumption by all residents. The volume of the septic tank must correspond to the amount of water consumed by residents in three days. Daily rate for one resident - 200 l. The final figure for the minimum internal volume of the septic tank is obtained by simple multiplication.
The resulting value is very important if you are building a sewer in a private house with your own hands. The scheme of the rings provides for the presence of 1-3 septic tank chambers. The number of wells depends on the composition of the family, the number of devices and mechanisms for sanitary purposes, and the intensity of their use. A three-chamber septic tank can be considered a real biotechnical complex. Its construction and maintenance will cost more, but the productivity and quality of wastewater treatment are significantly increased.
Of the three chambers:
- 1st - settling of accepted effluents;
- 2nd - purification of liquids (already clarified) from contamination;
- 3rd - filtering chamber.
In the treatment chambers, the lower concrete ring should be with a blank bottom to protect against leakage of liquid effluents that have not yet been cleaned. The third chamber is distinguished by the presence of a lower perforated ring, as well as a drainage layer at the bottom of the well. After passing through the drainage, the purified liquid is absorbed into the soil. In the predetermined walls of the rings, inlets are made to connect the wells with overflow pipes. In the first chamber of the septic tank, a hole is also prepared for the pipe coming from the house. This pipe must be below the freezing level of the soil. All pipes are laid with a slope to ensure gravity flow of wastewater.
Each connecting pipe leading to the next chamber must be below the level of the inlet for drains in the previous well. Violation of this requirement will lead to looping of the thread and incorrect operation of the system.
For all wells, round concrete slabs with holes for installing inspection hatches and ventilation pipes are purchased.
Drawing up a preliminary sewerage scheme helps to prevent possible errors, outline the procedure for performing work, make high-quality preparations for a set of construction activities, and calculate the amount of necessary products and materials.
Soil development
The pit for the chambers can be individual (for one well) or common, in which all the structures of a single system for receiving and treating wastewater will be erected.
For a separate well, the dimensions of the pit should be 25-30 cm larger than the diameter of the outer surface of the concrete ring selected for installation. The resulting gap will facilitate the installation and displacement of sewer rings using special equipment. The main disadvantages of such pits are: work with the soil is carried out manually, the impossibility of high-quality sealing of joints and waterproofing works from the outside of the rings with a sufficient depth of the structure being erected.
A common pit facilitates all types of construction work. With the use of special equipment, it will be ready in 1.5-2 hours.
At the installation sites of the receiving chambers, the bottom of the pit is rammed, laid with a waterproofing roll material (usually roofing material) and poured with a concrete mixture. Such a pedestal is not needed if the lower rings were purchased with a ready-made concrete bottom. At the site of the future installation of the filtration chamber of the septic tank, a crushed stone pillow is arranged (from 0.5 m). It allows the purified liquid to pass to the ground without obstacles and soak into it. In addition, such a pillow performs the final post-treatment of the liquid.
Installation of wells
Installation is obtained by installing the main and, if necessary, additional concrete rings on top of each other. To connect and seal the joints, special adhesives or cement mortar are used. When installing each concrete product, possible shifts or distortions are aligned.
Note! Installation with the use of lifting equipment and the involvement of assistants greatly simplifies and speeds up the construction process.
Final work
Holes for pipes are punched in the designated places of the concrete rings. A house drain pipe is brought into the first well. Then pipes connect all the chambers of the system. The joints are carefully sealed with mortar.
The next stage is the waterproofing of the joints of the rings, the junctions with pipes, the outer (and preferably the inner) surface of the concrete well.
Now each well is covered with a concrete cover, monolithic inspection hatches and ventilation pipes are installed. The work is completed by backfilling the soil into the remaining space of the pit with tamping the layers every 0.2-0.3 m.
The resulting sewerage from concrete rings, it was erected with its own hands or with the help of professional workers, will ensure the removal and high-quality cleaning of household wastewater, protect the soil and groundwater in the garden from pollution, and eliminate the inconvenience of living in a private house. An inexpensive and efficient treatment system will last at least 50 years.
Video review:
Everything useful about sewerage -
A person in a private house consumes water, energy, electricity, so there is a mandatory water supply and power line. And if there are garbage containers and landfills for MSW, then the question of where to put the drains is quite acute for the owner. There is no central sewerage system in most places where the private sector is located. It is much more expedient to build a sewer system in your area. As an example, sewerage from concrete rings. Work on its arrangement can be done by hand. And for this you need to familiarize yourself with the subject in detail.
- This is a variant of equipment for the collection and processing of wastewater from private households. In it, liquid waste is settled, cleaned, and the resulting liquid is removed in one way or another. Concrete rings serve as the walls of tanks in which waste accumulates. Since such containers are subject to special requirements for building codes, they must have strength and waterproofing characteristics. By itself, this is not an ideal material, it has both advantages and disadvantages.
What are the pros and cons of septic tanks?
One of the main pluses such a construction their price. Concrete is inexpensive compared to other materials. This allows you to equip and operate septic tanks from concrete rings in households with different income levels. Such a structure will last a long time, since concrete is also durable - stronger than the brickwork that used to serve as the walls of such devices before. He N not susceptible to oxidation and well withstands the force of the impact of the soil during frost heaving and internal pressure when topping up wastewater. Properly done work gives complete waterproofness. Other materials with the same characteristics (such as plastic containers) are much more expensive.
Such a septic tank has minuses. Among them, the main one that makes it difficult to carry out independent work is big weight materials and fragments. Installation will require either construction equipment, which needs to be provided with an unhindered entry to the site, or various devices that facilitate manual labor. Besides, completely alone, it is difficult to work with concrete without helpers. Another disadvantage is related to the properties of the concrete itself. Unfortunately, strength and hardness are combined in concrete with brittleness, from which even reinforcement with iron bars does not save. On the other hand, such an effect with well-chosen materials is possible only after a dozen or two years.
When they decide to create their own sewage system, according to a combination of factors a concrete septic tank still has more advantages, which makes it a popular solution on private lands and adjacent territories.
Sewerage device from concrete rings
Different types of systems from sections of a large-section concrete pipe have a common scheme.
This is a pipe buried in the ground, the walls of which consist of those very segments. In the upper part of such a composite tank there is an opening connected to the sewer pipeline, from where liquid waste, waste water, fecal matter, etc., come from. A little lower, but not at the very day, there is another hole - excess water flows out of it. Sediment usually falls at the bottom. At the top, at the end of the compartment, there is a hatch. Through it, they gain access to the septic tank in case of unforeseen circumstances or pumping out the contents when clogged.
Under normal conditions, upon reaching a certain level, the liquid drains either onto the ground or goes into the thickness of the earth. Depending on the number of sections in the septic tank, the following sewer systems are distinguished:
- single-chamber;
- two-chamber;
- three-chamber.
Each of these systems is applied taking into account the number of residents and the amount of waste they produce.
Single chamber septic tank
Such options are little used in private households designed for year-round use. This is due to the practical lack of processing capacity of such a device. It is made on the principle of a cesspool, only from modern materials and looks neater. The bottom of a single-chamber septic tank is either completely drowned out by an additional concrete slab, which, during installation, is lowered into the pit first, or without a bottom, so that the water goes into the ground, and the dry residue is pressed and partially composted.
It is possible to arrange such a "bottomless" septic tank only on sandy, well-drained soils, far from water sources. From a closed-type single-chamber bunker, the accumulated wastewater must be pumped out mechanically from time to time. It is clear that with intensive year-round use of the bathroom, toilet, washing machine and dishwasher, such a device simply cannot cope with the volume of sewage.
Prices for single-chamber septic tanks
Single chamber septic tank
Multi-chamber septic tank
In multi-chamber systems, two or three bunkers are assembled. They are connected by overflow channels. All containers, except for the last one, are of a deaf type, and have a spout only into the adjacent container. In the last barrel of concrete rings, either there is no bottom (recycled effluents are sucked up by the filtering layers of soil under the tank), or the output of the processed liquid to the filtering drainage field is equipped. Theoretically, the more bins, the better the wastewater is treated. In practice, more than three containers are not used.
The scheme of the device and operation of a two-chamber septic tank is based on the processes of settling and processing. The first container is made airtight, the effluent in it undergoes partial processing with the help of anaerobic bacteria, that is, bacteria that do not need oxygen. A hatch is traditionally made in the lid of the bunker. Cast iron lids continue to be the most popular option, but plastic lids are becoming more common. They are strong, light and not as brittle as cast iron. The second tank, also equipped with a hatch, has a ventilation shaft to the surface. The bacteria here are already aerobic, and chemical processing is added to biological processing - oxidation.
With a high level of groundwater, it is impossible to enter directly into the soil through natural soil filters. Then they arrange a drainage field - a piece of land, zoned and covered with loose stony materials of different fractions. Flowing down here, water seeps through the soil layer, being cleansed at the same time.
Prices for multi-chamber septic tanks
Multi-chamber septic tank
Step-by-step installation of a system with overflow
After the decision to make a septic tank with your own hands is made, you need to choose the right location for it. According to SNIPs, you need to place a septic tank at such a distance:
- from a well, a well - not less than15 m;
- from the edge of the lot — 2 m;
- from the nearest road — 2 m;
- from trees - more 3m;
- from home - no less 5 m.
Concrete bunkers should be lower than the level of the house and gradually go down. In the case of a completely flat area, such a slope is created artificially. Taking into account the requirements for the norms, you can proceed to the arrangement of a septic tank from concrete rings with your own hands
Video - Do-it-yourself septic tank made of concrete rings
Table 1. Specifications of concrete rings
| Name | Diameter (outer), mm | Height, mm | Weight, tons |
|---|---|---|---|
| KS20.12a | 2200 | 1190 | 1.68 |
| COP20.9 | 2200 | 890 | 1.48 |
| KS20.6b | 2200 | 590 | 0.75 |
| COP15.6 | 1680 | 590 | 0.66 |
Step 1. Drafting a project— the key to successful construction and subsequent operation. The volume of the structure should be calculated based on the total amount of wastewater that the family produces in three days. The average daily human consumption of water, which is drained into the sewer, is about 200 liters. That is, in a house for a family of three, the volume of the primary bunker should be 1.8 cubic meters. In this case, it is better to calculate with a margin and focus on 2 - 2.5 cubic meters.
The number of concrete rings is calculated based on the quotient of the total required volume divided by the volume in one concrete ring. Considering that standard sizes are produced, and their volume is given in the tables of technical characteristics, it is easy to calculate the number of parts required. For example, when using rings like KS-20-9 tall 89 cm and 0.56 cubic meters each, then with a margin you will need 5 rings. If you do at the rate of 2 cubic meters and leave a small margin, then you can get by with four per bunker.
Note! Also, when calculating, keep in mind that wastewater fills the tanks only up to the overflow line, so when calculating the design height of the bunker, the height to the roof will need to be done more.
Step 2. Selection of materials and tools. If you prepare everything necessary for arranging sewage in a private house in advance, the work can be carried out very quickly and without delay. Quantity different types material must be purchased in accordance with the project. In reserve, they usually add about 10% to compensate for possible overruns and costs of some types of work.
The main material is the concrete rings themselves. They come in different diameters, thicknesses and heights. Regardless of the type and parameters, it is recommended to choose rings with a lock for both the septic tank and the well. The castle is the inner step at the top of the ring and the outer step at the bottom. Such steps are obtained in special forms. When joining the lock rings, they enter into each other, like the details of the designer. The whole structure acquires the necessary rigidity and tensile strength and displacement. In regions with heaving soils, such a locking mechanism is very useful. In addition, this saves on fastening rings to each other.
Other materials that will be needed during construction:
- crushed stone of fine fraction;
- coarse sand;
- mortar based on a cement-sand mixture;
- materials for hydro- and thermal insulation;
- assembly foam.
In addition to the equipment with which it will be possible to lift and install the rings, you will also need hand tool:
- construction spirit level;
- a ladder for descending into an already dug pit and climbing out of it;
- perforator for drilling and slotting work on concrete;
- brush or maklovitsa;
- trough or tub for solution.
Elements that deserve special attention are overflow pipes. They can be made from asbestos cement or polypropylene. The latter are preferable, since they simultaneously possess such properties as strength, flexibility, durability and light weight. Unlike water pipes, where there is pressure and which require docking with a special apparatus, sewer pipes in 120 mm diameter are connected by means of a bell with a rubber seal.
Step 3. Digging holes for a septic tank and preparing them. A pit for a septic tank can be dug in two ways: manually and with an excavator. To work with a shovel, the forces of one or two people will not be enough, you will need to hire a whole team. Therefore, there will be no significant savings compared to the use of special equipment. The excavator is faster. Therefore, it is worth resorting to manual labor only if the access of equipment to the digging site is limited.
The diameter of the pit must be greater than the outer diameter of the concrete ring by 50 - 70 centimeters for waterproofing. The difference between the primary reservoir and each subsequent one is about 50 cm vertically. After the pits for all the tanks in the system are ready, they begin to tear off the trenches, where the supply pipes from the source will be placed. They are recommended to be buried below the freezing point of the soil. Crushed stone or sand is poured into the base and rammed well.
The bottom of the pits for septic tanks is concreted or simply covered with rubble. It depends on the ring underlying. If with a bottom, then it is enough to fill with rubble. If without a bottom, then you need to arrange a foundation. In any case, the gravelly pillow must be tamped down. The easiest way to do this is with a vibrating plate, but there are also manual rammers.
Step 4. Construction of the tank from the rings. The first ring with the bottom must be installed carefully in level, strictly vertically. Before installation, a layer of waterproof cement is applied around the perimeter. The ring crushes it with its weight, and then the cement is smeared with a trowel or spatula. On top of the first ring, subsequent joints are installed in the lock; it is also recommended to coat with a cement-sand mortar. The mass squeezed out of the joint is distributed over the surface. Installation is carried out with the help of a crane, and two or three people who will pull the lines and align the elements.
After the joints are treated with mortar from the outside and from the inside, the turn of waterproofing comes. The most convenient material is bituminous mastic. For its distribution, you will need a wide brush or maklovitsa. Mastic is smeared not only with cracks, but with the entire inner surface of the septic tank, which will be in contact with wastewater. This is done because the concrete gets wet during prolonged exposure to the liquid, and after that it begins to collapse.
A concrete cover with a smaller diameter hole is installed on top of the last ring by a crane. On it, you can either immediately mount the hatch, or bring out the neck with a height of about 50 cm. Then she alone will rise above the surface of the soil. In the second tank, where the presence of oxygen is necessary, it is necessary to provide a ventilation pipe up to 1 m above the soil surface.
Important! The cavity that remains between the walls of the column and the pit is covered with soil, sand and gravel. When backfilling, everything is rammed and filled with water. The upper part of the tank is insulated to avoid the formation of an ice plug in severe frosts.
Step 5. Installation of the overflow system. Wastewater must flow into the sewer system by gravity, so the exit from the house must be at the highest point. It is better to make the exit below the freezing point, then there will be confidence that the sewer will not freeze and will not clog. To bring the overflow pipe into the column, a hole is hammered with a perforator. After inserting the pipe, blow out the cracks mounting foam, and then sealed with a solution so that the foam does not deform. On sale there are special rings with ready-made inlets and outlets for overflow pipes. Tees are placed at the ends of the pipes for access for cleaning purposes.
Step 6. Organization of a filtering well or drainage field. At the final stage, water is drained with additional filtration. For this purpose, the bottom of the last container in the system is not made solid. The bottom is covered with sand, the top is filled with fine gravel. The largest fraction goes to the top layer of drainage. The lowest ring in such a well may have perforated walls.
If the groundwater level or soil composition does not allow water to be drained through a drainage well, a drainage field will be organized. From the last tank, water is discharged through perforated pipes. Pipe trenches are also covered with gravel or crushed stone, geotextiles are laid on top, and a layer of turf is placed on its surface.
Video - An example of a septic tank made of concrete rings WITHOUT the use of technology
Conclusion
As a result of the work, a durable and simple sewer structure is obtained, designed for 30 - 40 years operation. The greatest costs in the arrangement of a septic tank made of concrete, in addition to the main material, go to the rental of lifting and earthmoving equipment. On the other hand, this guarantees fast and mechanically precise work, regardless of the properties of the soil and the parameters of the reinforced concrete rings.
