When designing buildings and structures, among other things, all kinds of climatic factors of the area where the construction will take place are taken into account. Planning engineers must take into account, for example, parameters such as the level of groundwater location, the structure of the soil on the site and, of course, the depth of freezing of the soil. In the Samara region, as in all other regions of the planet, the latter indicator depends mainly on climatic conditions. That is, from air temperatures in the winter time, the thickness of the snow cover , etc. Also, the depth of freezing of the soil also depends on the characteristics of the latter. After all, the land on the site can be either clay or rocky or sandy.
Climate of Samara region
This region of the country is located in the zone of influence of the Asian continent. And in this part of the world, as you know, air temperatures in winter and summer vary significantly. However, the climate in the Samara region is still not as sharply continental as in Asia. The mitigating effect on it, as well as on most of the European territory of Russia, is provided by the Atlantic Ocean.
But in any case, the climate of the Samara region is characterized by low snowy and rather frosty winters. Their duration in this case is usually not less than 150 days a year. The average daily temperature in the Samara region in January ranges from -10.9 ... -13.8 . Therefore, the depth of soil freezing in this region of Russia is significant.
Rainfall in the winter season throughout the Samara region is distributed quite evenly. But still a little more snow falls in the northern part of this region. Here, in some cases, the soil may freeze to a lesser depth than in the rest of the region. But this difference, of course, is insignificant.
SNiP 23-01-99
Construction climatology is the branch of physics that considers the influence of climatic factors on buildings and structures. When designing and constructing buildings, the information set forth in SNiP 23-01-99 must be taken into account . This document was developed by NIISF specialists for all regions of the Russian Federation. In 2000, it replaced the previously existing set of standards for SIT 2.04-01-98.
Changes to the Construction and Climatology SNiP document drawn up at the beginning of the millennium were last made in 2003. In this code , among other things, a table of climatic parameters for different regions of Russia in the cold season is given. In the Samara region, according to this document, they are such as in the table below.
average temperature | Average humidity | Precipitation from March to November | Average wind speed |
From -4.3 to -8.5 | 84% | 176 mm | 4 m / s |
These and other parameters presented in SNiP should be taken into account when designing buildings and structures in the Samara region.
Building climatology: soil freezing depth
This is one of the most important parameters taken into account when designing a project. Depending on this indicator in a particular area, a decision is made not only on the depth of the foundation, but also on the choice of the variety itself.
Actually, the depth of freezing of the soil, in the Samara region, is also called the largest value at which the soil temperature is 0 ° C during the period of the lowest temperatures without snow cover, taking into account observations for many years. It is especially important to take this parameter into account on soil types such as loam and slurry.
Why is it so important to know the depth of freezing
As you know, when freezing, water always increases in volume. Soil in any case contains a certain amount of moisture. When the latter freezes, the soil begins to put strong pressure on the bottom of the foundation of the building or structure, "trying" to push it up. In the spring, the water thaws, and the building, together with the base, falls down again. As a result of these shifts, the foundation and other supporting structures of the house or structure are gradually destroyed.
When laying the foundation of a building below the freezing level, such a problem will not arise. Indeed, in this case, the sole of the foundation will be located at a level at which the soil temperature is never minus. That is, freezing water is simply impossible.
How to determine the depth of freezing soil
In order to find out at what exact point the temperature of the earth in a particular area never drops below 0 ° C, you can use special formulas. They are presented in another document, information and standards from which should also be taken into account when designing structures - SNiP 2.02.01-83.
The formulas of this document are quite complex. And therefore, the calculation on them is carried out mainly by specialists. For a private developer, if he does not want to hire engineers for the design, it would be better to use the information provided in the old SNiP 2.01.01-82. In this document, among other things, there are maps of the localities of the Russian Federation indicating the average values of the depth of freezing of the soil.
Formula
The depth of soil freezing is calculated for the Samara region and other regions of the Russian Federation, according to SNiP 2.02.01-82, using the following formula:
Here h is the desired depth, M is the sum of the absolute average monthly temperatures in this particular region, k is the coefficient of a certain type of soil. The last indicator can be found in a special table. So, for example:
for clay or loam, it is 0.23;
for large and gravelly sands - 0.3;
for fine and dusty sands - 0.28;
for coarse soil - 0.34.
By itself, this formula is quite simple. However, when designing, according to the new SNiP, in addition to the actual indicator of seasonal freezing of the soil, calculated with its use, it is also necessary to take into account such factors:
operating conditions and purpose of the structure itself;
total load on the foundation;
the depth of the foundations of nearby buildings;
soil parameters;
groundwater level.
Indicators for the Samara region
So, during the construction of a building or structure in this region, you should either calculate the freezing depth using the formulas, or simply use the map. The latter method is not too accurate. But at the same time it can be called the simplest. According to SNiP 2.01.01-82, for the Samara region the level of freezing of the earth is 160 cm. This is more than, for example, in Kaliningrad (70 cm) and even in Moscow (140 cm), but less than in Orenburg (180 cm ), Omsk (200 cm) and Khanty-Mansiysk (240 cm).
Dependence of freezing on soil type
It is known that fine sand usually freezes to a shallower depth than coarse and gravelly, and to a greater than loam. For the Samara region, the depth of soil freezing, depending on its type, will be as follows:
Thus, focusing on the average indicator for the Samara region of 160 cm is far from possible in all areas. First, you should determine the type of soil on the site. In some cases, the bottom of the foundation may need to be lowered lower, and in others, it should be raised in order to save material and labor costs.
Does the design take into account the thickness of the snow cover
The climate in the territory where the Samara region is located is quite severe. There is not too much snow here, and the air temperature drops strongly in winter. Actually, the freezing depth indicator itself, as already mentioned, does not depend on the amount of snow cover . When designing it is usually not taken into account. However, the owners of country houses in the Samara region in the process of their operation should pay attention to it. Of course, the thicker the layer of snow covering the soil, the less shall it freeze.
In the winter season, owners of private houses, clearing snow in the yard, unfortunately create zones of uneven freezing of the soil. This can even harm the foundation, designed without taking into account the thickness of the snow cover in a particular area. To prevent this from happening, it is worth planting bushes, for example, near the walls of the house. They will hold snow over the foundation, which will reduce the freezing of soil.
Shallow bases
Thus, such an indicator as the depth of freezing of the soil is actually very important. But usually only multi-story buildings or important structures are built with it in mind. Private traders in most cases prefer not to have the base of the foundation so deep. Shifts due to spring heaving in one-story buildings usually do not cause much harm to their base and load-bearing structures. But this applies only to those houses that are built on fairly reliable soils — clay or loam, rock, coarse sand. In this case, reinforcement is used to prevent the destruction of the foundation due to soil pressure. That is, a grid assembled from metal rods is poured into a tape or posts.
Concrete structures are able to withstand tremendous compression pressure. But in terms of stretching, they are quite reliable, unfortunately, are not. Metal fittings compensate for this drawback. Also, in order to increase the service life, finely buried foundations can in some cases be insulated using, for example, expanded polystyrene or expanded clay.