Why is it called shotcrete?  Shotcrete gets its name because it’s literally “shot” onto surfaces at high velocity using compressed air. This dynamic spraying process compacts the concrete as it adheres to the substrate, which is why the technique can be used on vertical and overhead surfaces without the need for extensive formwork.

   The word "shotcrete" combines "shot" (spraying) and "concrete", reflecting its application method: high-pressure spraying of concrete onto surfaces.  Initially called "Gunite" (referring to the dry-mix process) in the early 20th century, the term evolved to "shotcrete" as wet-mix technology became prevalent.

   Primary Applications

   ① Rapid Support and Reinforcement

   - Used in tunnels, mines, and underground structures for immediate stabilization to prevent collapses.

   - Repairs damaged structures (e.g., fire-affected concrete) to restore strength.

   ② Adaptability in Complex Environments

   - No formwork required; suitable for irregular surfaces (e.g., slopes, curved tunnels).

   - Enhanced with steel fibers or mesh for crack resistance and seismic performance.

   ③ Efficiency in Construction

   - Wet-mix technology reduces dust and rebound (5–10% rebound vs. 15–30% in dry-mix).

   - Robotic spraying improves productivity (3–5× faster than manual methods).

   These advantages make shotcrete a preferred method in many construction and repair applications.