Concreting the foundations

Concreting the foundations – Laying concrete with a concrete pump.

You need sand or gravel to arrange house drains. When ordering gravel - in addition to the amount needed to make the concrete mass – it must be brought in so much more, that there is enough for the leveling layer of thickness 5 cm under the footing or the foundation slab. Due to the leveling layer, mixing of fresh concrete is prevented, during its laying, with the highest layer of earth and its quality deteriorated. Often, a leveling layer of concrete with a thickness is additionally laid 5-10 cm, so that the reinforcement is covered with concrete. Then the reinforcement is placed. They are steel meshes or steel bars, whose parameters are consistent with the strength calculations. The specified stability standards must not be deviated from. The most frequently used mass is concrete brought from the concrete plant to the construction site, because thanks to this, the required quality of concrete can be fully maintained. However, when preparing the concrete mass manually, especially when it comes to larger amounts, the properties of the concrete may deviate too much. The concrete is delivered to the desired location by means of a truck concrete mixer truck, and concrete is transported by wheelbarrow to more distant places on the construction site. Sometimes a concrete pump has to be used, then less dense concrete should be used. The concrete thickens during the laying process and immediately thereafter. By carrying out the work in an economic way, this is achieved by tamping. Having the right tool, concrete can be compacted, also with a vibrator. When compacting by tamping, the concrete should be laid in layers with a thickness 15-20 cm, which becomes denser. The compacted surfaces of the single layers must be adjacent to each other, that the concrete compacts evenly and that there are no expansion joints. Concrete compaction is complete then, when water appears on its upper surface. After compacting, the surface is smoothed and checked with a spirit level. If possible, longer breaks in concreting should not be allowed, because then gaps can form. Tam, where it is inevitable, the concrete is joined diagonally or in faults. Before laying concrete further, the joint surfaces should be roughened and cleaned.

Foundation earth electrode
When concreting the footings of a residential building or garage, a foundation earth electrode is placed in them. It is a strip or wire of galvanized steel. Later, the home electrical wiring is connected to the grounding electrode. Electrical resistance of concrete, which is close to the resistance of the earth, provides good grounding. Concrete protects the foundation earth electrode against corrosion.