Boarding
Boarding
Lintel formwork
If concrete is laid, for example, in narrow-space excavations for strip footings made in scattered soil, trench formwork is needed. The formwork requires experience, because fresh concrete exerts great pressure on the floor and the deck walls. If the formwork is not stable enough and supported, may collapse when laying concrete. By making larger formwork, for example, the formwork of an inter-story ceiling in a residential building, consult a specialist. The formwork can be made of smooth boards or boards joined with a tongue and groove. Depending on the desired surface texture of the finished concrete element, raw or planed boards are used. Formwork shields are used for larger planes. These are ready-made boards of planed spruce boards of the 50 x 150 cm and thickness 22 mm, the front sides of which are connected by wooden beams or steel sections. They are suitable for many purposes on the construction site. In addition, plywood formwork boards and blockboards can be used. All formwork planks should be cleaned before use and free from any adhered concrete residues. To prevent concrete sticking to the formwork planks, before assembly, they are sprinkled with release agent. A particularly good separating agent is fat or oil. As a result, the adhesion of wood to concrete is reduced, which makes stripping easier. However, the reinforcing steel must not be stained with the release agent, because in this case the steel will not bond to the concrete. Wooden beams are used for the base of the formwork and for the supports. Steel pipe supports are extendable and their length is adjustable. To safely transfer the concrete pressure force to the ground, the supports must have a fixed base of wooden beams or thick boards. It is forbidden to use loose bricks for supports, barrels or other such auxiliary structures. In order to precisely align the supports, place them on double wedges, which then facilitate stripping. We always use double wedges, because a single wedge could cause the support to slip.
The supports stand on a thick board, their height is leveled with two wedges
