Influencing factors on the distance of the sewer pipes
When calculating the depth of the sewage pipeline, the following parameters should be considered:
- Technical parameters of the materials used in the construction;
- Specific features of the material used;
- The terrain on which work is being done;
- Climatic mark, regulated by the normative act of SNiP 2.01.01.82, which shows the annual freezing capacity of soils;
- When laying under the roads, it is necessary to take into account the maximum dynamic load.
Ground freezing
The average freezing on the regions is no more than( m):
- Loam, clay - 1,5;
- Dusty and fine sands - 1,9;
- Sands of large and medium size - 2;
- Large - clastic soils - 2,3;
Therefore, when starting the design of sewerage, determine the distance to which the soil freezes into which the system will be laid.
The soil freezing point is the maximum depth of the soil, below which the liquid in the soil does not crystallize, measurements are taken in standard units.
Below the freezing level, the soil volume does not increase due to freezing of the soil. Consequently, the system will not be physically affected. To clarify the level of freezing, it is possible to contact the local metrological service, where you can find out the indicators based on years of research on soil properties.
Taking into account the peculiarities of the construction of sewerage communications, there are some differences from the water supply systems. The depth of the laying of sewage pipes is calculated not by complex arithmetic calculi. The drains transport waste products of positive temperature, so from the value of the freezing point of the soil, subtract a certain value, which reduces the depth of the sewage pipeline. The value depends on the diameter of the drain:
- Using sewage pipes with a diameter of more than 0.5 m, this value will be 0.5 m. For example, the depth of freezing of the soil is 1.8 m, the depth of the sewer pipe will be 1.3 m( 1.8-0, 5 = 1.3 m);
- If the diameter of the pipes is less than 0.5 m, the value will be 0.3 m. Example, the parameters of the same construction, but with a pipeline diameter 0.4 m, the depth to which the pipe is to be laid will be 1.5 m( 1.8-0,3 = 1.5 m).
After the calculation phase, it is necessary to excavate the trench, into which the laying of communications will be carried out. In order to save on excavation, trenches must be made narrower. It is strictly forbidden to reduce the depth of the sewage pipeline.
Terrain and its features
Features of the terrain on which work is carried out, will affect the level of occurrence of sewage drainage. The construction of a sewerage system on a relatively flat land site will ensure a relatively uniform depth of the sewage pipeline laying along its entire length.
If the work takes place on the site with large differences in height, the depth of the sewerage line is measured from the lowest point of the site. When working on uneven areas, it is more expedient to build a straight pipeline at a constant depth with a certain slope.
When laying the sewerage system in the place of movement of people and cars, it is necessary to take into account the dynamic load on the polymer sewer pipeline. In such cases, the bookmark should be made using reinforced polymeric corrugated channels or in a closed way.
Sewer pipes and their technical characteristics
Plastic pipes are more modern than metal and ceramic pipes. This product has several advantages:
- Durability;
- Ease of installation;
- Acceptable cost;
- Easy transportation and more.
It is necessary to take into account the disadvantage of this product, this is the depth of laying sewage pipes in the ground is limited. And in order to avoid unforeseen circumstances it is necessary to carefully study the technical indicators that are declared by the manufacturer.
Strength calculations are carried out according to SP 40-120-2000, this document sets out the rules for the principle and installation of plastic sewer pipes.
When studying the technical parameters of materials from polymers, special attention should be paid to the level of the bookmark so that it corresponds to all the conditions of the project. If these parameters are ignored, the system can not withstand the pressure created by the ground, and will be damaged. What will entail the dismantling of the old pipeline and the laying of a new one.
Some Aspects of
The depth of sewer laying is a relative value that needs to be adjusted while taking into account the terrain, the length of the pipeline and the design features.
In gravity sewage systems, drainage to the wastewater treatment facility should be observed at a rate of 2 cm( 0.02 m) per running meter( that is, with a drainage length of 15 m, the depth of the pipe and septic connection point is 30 cm( 0.3 m)) deeper).
The level of the sewage system will ensure efficient and long-term operation, if the calculations are made qualitatively. Also knowing the indicators, it is possible to optimally lay the pipeline, which will reduce costs.
