What is sprayed on concrete called? The material sprayed on concrete is often called shotcrete or gunite. Both refer to a type of sprayed concrete, but they differ in their application methods:

　　--Shotcrete: Concrete （a mix of cement, sand, and aggregate） is sprayed through a hose at high velocity onto a surface. It can be either a dry-mix or wet-mix process.

　　--Gunite: Originally referring specifically to dry-mix sprayed concrete, where dry materials are mixed at the nozzle with water and then sprayed onto the surface. The term "gunite" is often used interchangeably with "shotcrete."

　　What is sprayed concrete used for? The primary applications of sprayed concrete include:

　　1. Tunnel Construction: Sprayed concrete is used to create the internal lining of tunnels, providing structural support and protection against collapses and water ingress.

　　2. Mine Support: In mining, shotcrete is applied to the walls of mines and shafts to stabilize them and prevent rock falls.

　　3. Underground Engineering: For subterranean structures such as basements, bunkers, and地铁站 platforms, shotcrete provides a quick and effective means of creating a protective barrier.

　　4. Road and Railway Construction: Shotcrete is used in road and railway embankments, cuttings, and retaining walls for erosion control and stability.

　　5. Water Control Structures: Dams, reservoirs, and other water storage facilities use shotcrete for sealing and reinforcing purposes.

　　6. Slope Stabilization: On slopes prone to landslides, shotcrete is used to add strength and reduce the risk of soil movement.

　　7. Concrete Repair and Rehabilitation: Existing concrete structures that have deteriorated can often be repaired by applying a layer of shotcrete to reinforce the damaged area.

　　8. Artificial Rock Formation: In some cases, shotcrete is used to create artificial cliffs or rock faces for aesthetic or functional reasons.

　　Sprayed concrete, also known as shotcrete or gunite, is a technique used in construction where a premixed material is sprayed at high velocity onto surfaces. It is widely used due to its ability to bond well with moist and non-moist surfaces, rapid application speed, and the fact that it can be applied to hard-to-reach areas or complex shapes without the need for formwork.

　　The advantages of using sprayed concrete include improved safety through reduced working at height, increased durability, and cost savings due to faster construction times and less labor intensity compared to traditional casting methods.