What is the main technology of permeable concrete admixture? How is the technology implemented?

The so-called permeable concrete mainly uses single-grain extremely coarse aggregate as the skeleton, and a thin layer of cement slurry or mortar with a small amount of fine aggregate is wrapped around the surface of the coarse aggregate particles as a cementing layer between the aggregate particles. , a porous concrete material that forms a skeleton-pore structure. What is the main technology of permeable concrete admixtures? Permeable concrete is an ecological and environmentally friendly concrete with continuous pores, good air permeability and water permeability. While ensuring its strength and excellent water permeability, it can be designed and manufactured in different color combinations as desired. The color of the pavement complements the buildings, beautified vegetation, and surrounding landscape, showing a beautiful and pleasant landscape charm.

Preparation: While permeable concrete meets strength requirements, it also needs to maintain a certain through-hole to meet water permeability requirements. Therefore, in addition to selecting appropriate raw materials during preparation, it is also necessary to design and mix the mix ratio. The preparation process and additives are used to ensure strength and porosity.

Construction: The construction of permeable concrete mainly includes paving, shaping, surface treatment, joint treatment and other processes.

Maintenance: Cover and maintain the permeable concrete after construction, spray water and moisturize for at least 7 days. During the maintenance period, the pores on the concrete surface should be prevented from being contaminated by sediment.

Permeable concrete (Porous Concrete) is a semi-rolling dynamic concrete made of single-grain aggregate, cement, pure pigments, admixtures and water in a specific proportion through a mixing process. Occasionally, a small amount can be added Sand. It is a high permeability, high strength, environmentally friendly ground paving material that is paved on-site using unique machinery.

The development history of permeable concrete

The application of permeable concrete began More than 100 years ago, according to V M Malhortra's records: In 1852, Britain developed concrete without fine aggregates, namely permeable concrete, in construction projects. The United States has begun research on permeable concrete design methods since the 1960s. In 1995, Nader Ghafoori of Southern Illinois University elaborated on the use of permeable concrete as a pavement material and studied its physical properties. Later, other countries such as Japan and France also began to conduct research and development on permeable concrete.

Our country began research on permeable concrete and permeable concrete pavement bricks in 1993, and successfully developed permeable concrete in 1995. With the expansion of the application scope of permeable concrete, my country has introduced a series of specifications and standards since 2009, such as CJJ/T 135-2009 "Technical Regulations for Permeable Cement Concrete Pavement" and Standard Atlas 10MR204 "Urban Roads - Permeable Pavement Paving" wait. Some regions have also introduced some local standards

Permeable concrete admixtures, also known as reinforcing agents, are a type of powder material processed by adopting internationally imported pure formulas and combined process configurations; admixtures have the ability to improve the performance of permeable concrete. The bonding function between aggregates participates in the hydration reaction of cement to form high molecular polymers, which greatly improves the "point bonding" strength between aggregates, and at the same time plays the role of reducing water and retarding setting, so that the concrete material It has appropriate cohesion and does not flow during construction; the unique polymer admixture for permeable concrete effectively improves the lubricity and plasticizing properties of the mixture, making it more conducive to paving operations in limited areas. Highly permeable concrete compression and load-bearing performance.

Permeable concrete admixtures are added to the mixer together with cement, gravel, and water. Mixing like ordinary concrete can achieve the required construction workability and strength. Add cement. Permeable concrete with 4% reinforcing agent has a bearing capacity of up to 35MPa.

It is mainly suitable for light-load routes, squares and parking lots in new, expanded, and reconstructed urban route projects, outdoor projects, and garden projects. The pavement of the field, etc. Today, through years of research and development and application, the environmentally friendly building material permeable concrete of Baishi Manufacturer has begun to become a complete and mature design and construction process.

Permeable concrete construction process ：

　a. Lower layer management: Clean the lower layer mouth, which should be free of dust, branches, paper scraps and other debris, and moisten the lower layer mouth before paving.

b. Cloth : When paving permeable concrete, the reserved height for vibration should be considered. When permeable concrete is artificially spread, use a shovel to buckle it, and throwing is strictly prohibited. When paving permeable concrete for longer than 30 minutes or in windy weather, the concrete on site must be covered with plastic sheeting in time. , in order to prevent the permeable concrete from losing moisture too quickly.

c. Vibration: After the plain layer of permeable concrete is laid, use a scraper to smooth it, and use a flat vibrator to vibrate. The vibration is completed. After that, the surface layer of warm-colored permeable concrete or warm-colored exposed aggregate permeable concrete is paved, and then leveled, and the areas lacking material are replenished in real time, and the unique permeable concrete configuration is used for oral vibration and leveling until it is the same height as the formwork.

d. Oral finishing: The corners of the permeable concrete on the rolled pavement should be decorated in time. The areas lacking material should be filled and trimmed. For the drier areas, a layer of water can be sprayed evenly first, and then trimmed with material.

The above is about permeable concrete admixtures. I hope it will be helpful to you!

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