Foundations feed shallow burial

Shallow strip foundations are especially popular in the construction of low-rise country houses. They are versatile, reasonably available and do not require the use of special equipment. How to build a reliable shallow foundation? This article is devoted to this issue.

In what cases is it permissible to use a strip foundation.

This type of foundation base is common in private construction due to a number of advantages:

• Availability;
• Minimum earthworks;
• Applicability on various types of soil;
• Availability of building materials.

This type of foundation is ideal for the construction of buildings up to 3 storeys high, regardless of the building material used. Tape attachments can be used on heaving and non-heaving soil. Its use on clay and peat soil is not allowed.

Types of strip foundation

MZLF are of prefabricated and monolithic type.

• A monolithic strip foundation is a reinforced concrete strip located along the entire perimeter of the future building exclusively under the load-bearing walls.
• The prefabricated strip foundation consists of reinforced concrete blocks, which are fastened together with cement mortar. The device of such a base takes less time.

Sometimes a combination of a strip base and a pile base is acceptable. The support of the tape is carried out on piles, and under the tape itself it is necessary to make a crushed stone pillow. Pile foundations are used, as a rule, on soft ground or in areas with a difference in height.

The sequence of the construction process

Before the device of the tape, geodetic surveys are mandatory, which make it possible to determine the depth of soil freezing, its composition and the depth of the groundwater. Based on the above parameters, the type of foundation is determined. In order to save on expensive expertise, it is allowed to drill holes at several points on the construction site, which helps to independently determine the type of soil.

The procedure for the device strip foundation

• First, the construction site is cleared of vegetation and debris.
• Further, the fertile soil layer is removed.
• When the site is cleared, you can proceed to the marking - the dimensions of the future building are transferred to the construction site. To do this, mark the front wall of the house, facing the side of the street, after two walls perpendicular to it. To determine the evenness of a rectangle, it is necessary to compare its diagonals. Beacons are installed in all corners. It is convenient to apply dimensions directly to the ground using a lime mortar.
• Next, digging of a trench begins.

Trench parameters

• The depth of the shallow strip foundation trench is 500 mm.
• Width 300 mm.

The pillow is made of rubble or sand. A two-layer version is often used. It is necessary to lay geotextiles on the dusty soil in front of the device.

The pillow is poured in layers, each layer needs to be well compacted. When using sand and crushed stone, 100-150 mm of sand is initially filled in and compacted. To facilitate this task, the sand is moistened with water.

The nuances of building a monolithic foundation

After the trench is ready, the formwork is installed. For its device, you can use ordinary boards or knocked down wooden shields. The height should be slightly higher than the required concrete pouring level.

The shields are fixed with special pegs. Fasteners should not "look" into the inside of the installed formwork. Their presence in concrete can provoke the development of cracks and lead to chipping off of pieces of concrete.

The formwork is reinforced with spacers. They are installed from the outside at a distance of no more than 500 mm.

The inner part of the formwork is covered with a foil, which prevents excessive evaporation of moisture from the concrete mixture and facilitates the process of dismantling the wooden elements.

Reinforcement

The device of the reinforced frame is an integral part of any concrete work. The connection of the reinforcing rods is carried out using a knitting wire. Welding is not recommended due to the high likelihood of corrosion.

Particular attention should be paid to the reinforcement of the corner parts of the frame. The rods must be bent so that the reinforcing bar goes over another wall with a length of at least 40 rod diameters.

Concreting

Better to use factory-made concrete. When preparing the mixture yourself, it is recommended to use a concrete mixer.

The concrete should be poured in layers, each of which must be compacted with a deep vibrator.

At the end of the work, it is recommended to sprinkle the concrete surface with dry cement. This will ensure quick setting of the top layer. If the work is carried out at subzero temperatures, the foundation is insulated using a special film and electric heating.