Concrete finishing is the process of compressing, flattening and polishing the newly poured concrete surface to form a smooth, beautiful and durable concrete slab.
The procedure must start immediately after pouring the concrete. It is done using special concrete finishing tools, the choice of which depends on the appearance of the surface you are aiming at and the type of concrete you are using.
Concrete Darby-This is a long, flat tool with two handles on a flat plate with a slight lip on the edge. It is used to smooth concrete slabs.
Concrete dressing trowel-used for final leveling of the slab at the end of the dressing procedure.
Concrete finishing brooms-these brooms have softer bristles than ordinary brooms. They are used to create textures on boards, for decoration or to create non-slip floors.
When pouring concrete, a group of workers should use square shovel or similar tools to push and pull the wet concrete into place. The concrete should be spread over the entire section.
This step involves removing excess concrete and leveling the concrete surface. It is finished using straight 2×4 lumber, usually called a screed.
First place the screed on the formwork (obstacle that holds the concrete in place). Push or pull 2×4 on the template with the front and back sawing action.
Press concrete into the voids and low points in front of the screed to fill the space. Repeat the process to completely remove excess concrete.
This concrete finishing procedure helps level the ridges and fill the space left after the leveling process. Somehow, it also embedded uneven aggregate to simplify subsequent finishing operations.
It is done by sweeping the concrete over the concrete in overlapping curves to compress the surface, pushing down to expand and fill the space. As a result, some water will float on the board.
Once the water disappears, move the trimming tool back and forth along the edge of the template. Raise the main edge slightly.
Make long strokes while processing the aggregate backwards until a smooth rounded edge is obtained along the boundary of the board with an edger.
This is a very important step in concrete finishing. It involves cutting grooves (control joints) in the concrete slab to prevent inevitable cracking.
The groove works by guiding the cracks, so that the appearance and function of the concrete slab are minimally damaged.
Using the grooving tool, grooving at 25% of the concrete depth. The span between the grooves should not exceed 24 times the depth of the board.
Grooves should be created at every inner corner of the concrete slab and every corner that touches the building or steps. These areas are prone to cracks.
This is the final polishing procedure designed to bring the best quality concrete to the surface to obtain a smooth, durable surface. This is done by slightly raising the leading edge while sweeping the magnesia float in a large curve across the concrete surface to compress the slab.
Although there are many types of floats that can do this work, including aluminum floats; laminated canvas resin floats; and wooden floats, many builders prefer magnesium floats because they are light and are very suitable for opening concrete holes. Evaporate.
Raise the leading edge slightly while sweeping the concrete finishing trowel across the concrete surface in a large arc to further compress the surface.
A smoother finish can be achieved by two or three passes through the surface-wait for the concrete to dry a bit before the next sweep, and raise the main edge a bit with each stretch.
Care should be taken to avoid applying too deep or “aerated” concrete mixtures, as this will release air bubbles in the material and prevent it from setting properly.
There are many types of concrete finishing trowels that can be used for this task. These include steel trowels and other long-handled trowels. Steel trowels should be used with care, because the wrong time can cause the steel to trap water in the concrete and damage the material.
On the other hand, larger trowels (fresnos) are great for working on wide surfaces because they can easily reach the center of the slab.
Brooms or decorative finishes are finished with special brooms, which have softer bristles than standard brooms.
Drag the wet broom gently across the concrete in batches. The concrete should be soft enough to be scratched by the broom, but hard enough to keep marks. Overlap the previous part to ensure completion.
When finished, let the surface cure (dry) to achieve maximum strength. Although you can walk on the concrete three or four days after completion, and drive or park on the ground within five to seven days, the concrete will not fully cure until the end of 28 days.
It is recommended to use a protective sealant after about 30 days to prevent stains and extend the life of the concrete slab.
2. Trowel finish-this easily becomes the most common type of concrete finish. The concrete finishing towel is used to smooth and level the surface of the concrete slab.
3. Pressed concrete veneer-this type of veneer is obtained by pressing the desired pattern on the freshly smoothed concrete surface. It is commonly used for driveways, sidewalks, and patio floors.
4. Polished finish-This is obtained by grinding and polishing concrete slabs with special chemicals to provide the ideal texture with the help of professional equipment.
5. Salt decoration-This is achieved by using a special roller to insert rough rock salt crystals on the newly poured concrete slab and washing it with plenty of water before the concrete sets.
Other common types of concrete finishes include exposed aggregate finishes, colored finishes, marble finishes, etched finishes, swirl finishes, dyed finishes, carved finishes, glitter finishes, covered finishes, and sandblasted finishes .
Post time: Aug-29-2021