The pile base for the house, which has a reinforced concrete beam laying on the upper crossbars, is called the grillage foundation, it can be built independently.
If the features of this support are considered, then the beams connecting the piles are distinguished. The grillage is designed to combine the foundation into a single design, and therefore the weight of the whole house is evenly distributed to all piles. Further, the entire load is transferred from the structure to the soil (to its strong layers located in the depths).
Basically, the grillage is arranged in the form of a monolithic, reinforced concrete structure, and its strength is provided by a metal frame made of reinforcement. In order for the load on the piles to be distributed evenly, the lower part of the grillage is located on weight, that is, on a mark located above than the zero level of earth.
Types of bases with a fundamental beam
The pile-rowing base can be of different types that differ in the used piles and the method of erecting a grillage. To arrange this foundation, clogging, screw, brownish or hanging shopuntes are used. And the grillage is in the form of a monolithic, reinforced concrete tape or has a prefabricated structure.
For buildings and structures made of light material, but located on fragile soil, a brownibular foundation with a grillage is used, which can be built on its own. This base is chosen when:
They want to save 30% of finances;
The peculiarity of the soil on the site and the occurrence of groundwater does not make it possible to equip another base;
a small load goes from building to the foundation.
Consider the advantages of this basis:
its device needs less time and finance;
reduces thermal losses, since the grillage does not touch frozen soil (if the space under it is insulated);
Vibration decreases.
Among the shortcomings are highlighted:
the location of the piles at great depths;
The space formed under the grillage must be filled and insulated.
How to make the foundation yourself
Consider an example of the manufacture of a grillage foundation with a bored piles that can be made by concreting wells located and drilled on the site. A monolithic grillage of reinforced concrete is arranged in supports.
Before working on the construction of the base begins, they cleanse and plan a site, and mark the placement of the axes and drilling places, and proceed to construction.
In order to make the foundation, brownish piles with a grillage are made independently. For this, for them, along the perimeter of the future house, in places of placement of the internal load -bearing wall, wells are drilled, and at the same time observe the step 2m. Their depth is: the level of freezing of the soil in a particular region plus 0.5 m (0.2 – sand pillow, 0.3 – pile).
This work is carried out using special equipment or manual drill, which can drill 5 m well with a radius of 15 cm. The depth and diameter of the holes are calculated based on the type and characteristics of the soil, more often their dimensions are 10 m by 0.2 m (respectively).
Next, the piles are made. A waterproofing material (PVC film, roofing material, galvanized, plastic or asbestos -cement pipes) is laid along the entire length of the drunk hole (PVC). If the last two materials are used, then their diameter should coincide with the well. Waterproofing is set above the level of soil, but accordingly the height of the piles. For this, the level is used.
After that, a reinforcing cage is installed in the well, consisting of 3-4 rods connected by transverse clamps. Its upper end should be connected to the grillage, so it is made above the piled piles. All elements are tied with soft steel wire. Between the waterproofing material and the frame make a gap in 2cm. This is necessary in order to fill it with concrete solution during pouring.
After this process, everyone ramms. Why is the construction vibrator are used. To grasp concrete and a set of strength, you need 1 month.
Although the grillage foundation with your own hands can be made of reinforced concrete, prefabricated elements or in the form of a monolithic belt, for it, the second option is most often used, since it is easier to install.
First put the formwork, so that 10 – 20 cm distance remains from soil to grillage. The width and height of the form corresponds to the size specified in the project. The reinforcement is installed inside the formwork, and its lower row is laid on the stand up to 3 cm, and this ensures its complete immersion in the solution.
From the side wall of the shape to the frame, the distance should be 2.5 cm. Grillage and reinforcement are connected using a special wire, making the outlets of the rods. Only after that they fill the foundation.
In order for the hardening of the concrete solution to occur evenly, in hot weather, grillage, periodically moisturize. Two weeks later, the formwork is removed.
Conclusion
The article tells how to make a grillage foundation yourself, what materials and equipment are needed for this case. But if before that they did not have experience in construction, or did not erect a house “from scratch”, then it is better to seek help from the specialists who will prepare the project, make all the necessary calculations and erect a quality house in a short period of time.