Because of its distinctive appearance and long lifespan, exposed aggregate concrete, commonly referred to as washed concrete, is a popular choice for numerous construction projects. This kind of concrete has a textured appearance that can improve the visual appeal of different structures because it has visible stones and pebbles on its surface. When it comes to patios, walls for decoration, driveways, and sidewalks, washed concrete mixes durability and design.
A number of critical steps are involved in the production of washed concrete, all of which are necessary to achieve the desired finish. Choosing the appropriate aggregate, cement, and water mixture is the first step. The unique appearance of washed concrete is largely due to the aggregates used, so choosing premium stones and pebbles is crucial. To shape the concrete, these ingredients are combined and poured into molds or forms.
The top layer of the concrete is carefully removed to reveal the aggregates underneath once it has been placed and allowed to set. To guarantee that the aggregates stay firmly embedded in the concrete and produce an even and appealing surface, this step calls for timing and precision. This can be accomplished in a number of ways, such as by brushing, water washing, or applying chemical surface retarders to postpone the top layer’s hardening.
Concrete is frequently sealed to preserve the surface and improve appearance after the aggregates are exposed. These sealants can help ensure that the cleaned concrete keeps its appearance for many years by preventing staining and weather-related damage. The lifespan and aesthetic appeal of washed concrete surfaces can be further increased with proper maintenance, which includes routine cleaning and resealing.
Washable concrete has several useful advantages in addition to lending elegance to your building project. Better traction is provided by its textured surface, which lowers the possibility of slips and falls. Furthermore, you can achieve the ideal appearance to match your design vision thanks to the variety of aggregates that are available for customization.
| Step | Description |
| 1. Mix Ingredients | Combine cement, water, sand, and gravel in a concrete mixer. |
| 2. Pour Concrete | Pour the mixed concrete into molds or forms. |
| 3. Initial Curing | Allow the concrete to begin setting for a short period. |
| 4. Surface Washing | Spray water on the surface to expose the gravel while the concrete is still wet. |
| 5. Final Curing | Let the concrete fully cure and harden. |
Exposed aggregate concrete, commonly referred to as washed concrete, is a decorative method that blends style and longevity. Concrete is mixed with aggregates during the manufacturing process, poured into forms, and the top layer is then washed away to reveal the decorative stones underneath. This technique improves the strength and slip resistance of the concrete while also producing a distinctive and beautiful surface, which makes it a great option for patios, walks, and driveways.
Manufacturing Features
The process of washing away the top layer of the cement-sand mass results in washed concrete. As a result, the solution’s internal filler is visible on the exterior, giving natural stones like pebbles, granite, or marble their texture.
It is possible to create structures with intricate geometries using the same technology. It is important to keep in mind, though, that these products will require additional concrete coating with a unique varnish and gel.
You don’t need to purchase specialized equipment to prepare this material yourself, so creating decorative elements for your suburban area is simple. All you have to do to accomplish this is research the technology required and how it is used to create washed concrete.
What is required
To create ornamental building materials, gather the following:
- water;
- sand (any);
- filler with a fraction of 5 to 20 mm (crushed stone, granite chips, marble, dolomite);
- cement (grade M 400 and higher);
- retarder for concrete mix (Peramin R, G-05, Cementol Retarde or any other);
- container for mixing the solution;
- water pump or spray gun with compressor (for making a path for a suburban area, a regular whitewashing pump will be enough);
- ready-made plastic or homemade wooden forms;
- concrete mixer;
- vibrating table (preferably);
- sprayer for applying retarder.
Practical! An inertial concrete mixer is preferable if you’re preparing a solution for a big structure—a "bulb" won’t do. Concrete can be manually mixed to prepare a small volume of the mixture.
Practical! You can use regular sugar syrup or detergent in place of an expensive gel hardener.
Now that you have everything ready, you can get to work.
Production process
The following is the standard technology used to produce washed concrete:
- Prepare a concrete mixture by mixing 1 part Portland cement, pebbles, 3.5 parts filler, 1.5 parts sand and water until you get a creamy consistency. It is important that the solution does not turn out too thick or too liquid if you are making small elements. For concreting the site, it is better to prepare a denser mixture.
- Apply a hardening retarder gel to the bottom of a plastic matrix or wooden formwork. The concentration of the deactivator will depend on temperature conditions, so it is better to experiment first.
- Pour washed concrete into the mold.
- Wait until the solution “ripens”. In order to determine its hardening time, study the instructions for the retarder. For example, when using gel G-05, the curing time will be from 20 to 24 hours. In this case, the deactivator penetrates the composition to a depth of 2-10 mm.
- If you have a vibrating table, use it to compact the concrete.
- Remove the product from the mold and place it on a flat surface so that the side to be washed is on top. You should not remove the product from the formwork ahead of time, otherwise the filler will be exposed, and it will simply begin to fall out of the concrete mass. You should also not remove the elements from the matrices too late, since in this case you will significantly complicate the washing process.
- Direct a strong stream of water onto the product, which will wash away the unset part of the composition, which contains the retarder gel.
All phases of the work must be completed quickly in order for the finished product made from washed concrete to be strong. As soon as you remove the workpiece from the mold, it needs to be washed.
It’s important to take note of the uniqueness involved in producing goods with intricate patterns. In this instance, it is required to submerge the completed product in the gel after the workpiece dries in addition to applying a retarder to the inner walls of the matrix.
There are practical and aesthetic benefits to the process of making washed concrete. This kind of concrete offers a distinctive and eye-catching finish by meticulously choosing and combining aggregate materials, then exposing them using a washing process. In addition to improving the concrete surface’s aesthetic appeal, washing it also gives it more durability and texture.
In particular, washed concrete is prized for its adaptability and non-slip qualities. It is frequently utilized in outdoor areas where aesthetics and safety are equally crucial, like driveways, patios, and walkways. The exposed aggregates give the design a natural, rugged appearance that complements a variety of landscape styles.
All things considered, the process of manufacturing washed concrete is a simple but efficient way to get a strong and attractive concrete surface. For both residential and commercial projects, homeowners and builders who want their building materials to be beautiful and functional continue to favor washed concrete.
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