One of the most reliable structural solutions for the construction of foundations for buildings and structures is a monolithic concrete foundation. To increase its technical indicators in terms of strength and resistance to various loads, it is reinforced with metal reinforcing cages.
In buildings where the basement is not provided, side trench walls are used as formwork. But it should be borne in mind that with such a technology for the production of work, an increased consumption of concrete is observed, which is economically disadvantageous. A well-established and firmly fixed formwork will provide a reduction in concrete mix losses , as well as fix the thickness of the structure, which is required by the design drawing on a monolithic strip foundation.
The installation of formwork panels made of coniferous wood is carried out on a sand cushion.
For formwork fastening elements, the use of hardwood is permissible. In accordance with the production technology, the width of the boards for the manufacture of panels should not exceed 150 millimeters. Boards should be the same thickness. The surface of the board in contact with concrete is covered with a film of polyethylene or sheathed with tin. It is forbidden to use formwork panels that have gaps between the boards to prevent the flow of cement milk.
A monolithic foundation is reinforced, depending on the bearing capacity of the soils located at its base. For the production of reinforcing frames, hot-rolled reinforcement of a periodic profile is used. For each individual reinforcing cage , the project indicates the size, brand and diameter of the reinforcement used. If the diameter of individual rods is up to 25 mm, they are fastened into a single frame by a special wire, spot welding or plastic fasteners, if more than 25 mm, then by electric arc welding.
Immediately before pouring the monolithic foundation, the formwork must be cleaned of deposits of dirt, debris, the fittings must be cleaned of rust. Slots should be removed.
The production of concrete works includes the following technological operations: production and delivery of concrete mix to the object, its laying into the formwork and care during the setting period. A monolithic foundation meets its technical parameters only if it is made of high-quality concrete mix. Its quality depends on many factors: brand of cement, aggregates, amount of water and many others. Monolithic tape foundations are concreted in a continuous way, but in case of emergency, this process can be interrupted with the obligatory arrangement of working joints. Working seams are performed only horizontal or vertical type, it is strictly forbidden to make them inclined. To achieve the best effect when performing monolithic foundations, it is mandatory to vibrate the concrete mixture.