Washed Stone Construction Process Shared by Washed Stone Manufacturer

❶ Foundation ➜ ❷ Leveling ➜ ❸ Mixing ➜ ❹ Smoothing ➜ ❺ Curing ➜ ❻ Cleaning ➜ ❼ Finished Product Protection

(1) Foundation

Later-stage problems in the construction of washed stone often revolve around cracking, and these are primarily caused by issues in the foundation. There are two common types of cracking: settlement cracking and expansion cracking. Repairing localized cracks can result in significant losses in terms of both effectiveness and cost. Therefore, when undertaking foundation construction, it is crucial to pay attention to the following points:

a. The compaction coefficient of the plain soil should be greater than 0.93. If the soil quality is too poor, replacement of the soil might be necessary;

b. Use a conventional crushed stone cushion layer with a thickness of 100mm. If this is insufficient, it can be increased to 150mm and compacted again.

c. The concrete base should have a thickness of 100mm and include a double-sided reinforcing steel bar of Ø8@200. It's important to note that the reinforcing steel shall be placed above the concrete base during the casting process and not laid flat on top of the crushed stone.

d. Expansion joints should be placed at intervals of 5-6 meters.

(2) Leveling

It refers to applying an additional leveling layer on the finished foundation surface. This is done for three main purposes: 

a. Control the elevation;

b. Control the thickness of the exposed aggregate concrete and save the costs;

c. Readjust the curvature of the previous foundation to ensure a smooth and flowing curve for the water-washed concrete.

(3) Mixing

During this process, aggregates, white cement, and color pigments are mixed in specific proportions to achieve a uniform blend. Pay attention to the following points:

a. Priming: Brush a layer of white cement slurry (milk-like consistency) on the leveled base to enhance the adhesion between the washed stones and the substrate;

b. Material Selection: Aggregates with a particle size of approximately 4-6 cm are preferred, and white cement with an original factory production grade of 42.5 should be used. This not only shortens the curing time but also enhances the bond between the stones and cement, preventing stone detachment in the later stages.

c. Proportion: The proportion of white cement to aggregates should be approximately 1:2. It is critical, because a mixture that is too thin may result in poor visual appearance, while a mixture that is too dense can lead to stone detachment later on.

d. Expansion Joint Treatment: Use a 2 cm wide transparent plastic strip as a separation joint.

e. To ensure the integrity of the washed stone edges, copper strips or PE separating bands can be used for the junction between the surface of washed stone and other paving materials.

(4) Smoothing:

Smoothing is the process of spreading and leveling the mixed cement and stone aggregate. The following points should be noted:

 a. The surface layer thickness of the washed stone is about 2cm, with a slight 2mm elevation in the middle (when laid on the ground) to ensure proper drainage;

 b. Round off the edges to a height of about 5cm to prevent the exposure of concrete or cracking at the edges of the washed stone. This is a meticulous and time-consuming step that shall be strictly followed;

 c. The frequency and force of smoothing are critical, directly affecting the density of the stone distribution. Typically, smoothing should be done 3-4 times, until no more water comes out. If the pressure is too light, the stones may accumulate unevenly, but if it's too heavy, the stone density may become sparse. This requires some level of experience on the part of the workers.

d. Smoothing Tools: 3-5mm thick iron plates should be used; plates that are too thin may not provide enough force.

(5) Curing:

Curing Time: After smoothing wash with water after 2 hours on a sunny day or 4 to 5 fives on cloudy or rainy day.

(6) Cleaning:

After curing is complete, wash off the top layer of cement with a soft brush. Ensure that the depth of exposed stones is about one-third of the surface depth, and that they do not come loose.

(7) Finished Product Protection:

After cleaning, let it air dry briefly and then proceed with the finished product protection. Start by covering it with a plastic sheet for moisture retention, then add a color strip cloth and secure it with nails on both sides. People can walk on it 24 hours after this process.

Anhui Huiliao Building Decoration Engineering Co., Ltd. is a large integrated enterprise that integrating GRC manufacturing, UHPC manufacturing, and washed stone manufacturing. It specializes in the research, design, production, and installation of GRC, GFRC, HPC, and UHPC architectural decorative materials, and is an highly influential company in the GRC industry.