One of the most reliable design solutions for building foundations for buildings and structures is a monolithic concrete foundation. To increase its technical performance 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 taken into account that with this technology of work, an increased consumption of concrete is observed, which is economically unprofitable. A well-installed and firmly fixed formwork will reduce the loss of concrete mix, as well as fix the thickness of the structure, which is required by the design drawing for a strip monolithic foundation.
The installation of formwork panels made of coniferous wood is carried out on a sand cushion.
Hardwood can be used for formwork fixing elements. In accordance with the production technology, the width of the boards for the manufacture of shields should not exceed 150 millimeters. Boardsmust be the same thickness. The surface of the shield in contact with concrete is covered with a polyethylene film or sheathed with tin. It is forbidden to use formwork panels that have gaps between the boards to prevent the flow of cement laitance.
A monolithic foundation is reinforced depending on the bearing capacity of the soils at its base. For the production of reinforcing frames, hot-rolled rebar of a periodic profile is used. For each individual reinforcement cage in the project, the size, brand and diameter of the reinforcement used are indicated. If the diameter of individual rods is up to 25 mm, they are fastened into a single frame with special wire, spot welding or plastic fasteners, if more than 25 mm, then using electric arc welding.
Immediately before pouring a monolithic foundation, the formwork must be cleaned of layers of dirt, debris, and the reinforcement must be cleaned of rust. The gaps must be fixed.
Concrete work includes the following technological operations: production and delivery of the concrete mix to the facility, its laying in the formwork and maintenance 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. The monolithic tape foundation is concreted in a continuous way, but in case of emergency, this process can beinterrupt with the obligatory device of working seams. Working seams are made only of a horizontal or vertical type, it is strictly forbidden to make them inclined. To achieve the best effect when making monolithic foundations, it is imperative to vibrate the concrete mix.
