What is the maximum aggregate size for shotcrete?

The maximum aggregate size for shotcrete is typically 19 mm. This size is frequently used because it allows the shotcrete mixture to achieve a good balance between workability and strength. Using aggregate that is too large can hinder the application process, as it may not allow the material to adhere properly to the substrate or may cause issues during the spraying process.

Smaller aggregates facilitate a smoother application and enhance the material’s ability to fill gaps and voids effectively, contributing to a denser and stronger final product. It's also worth noting that common codes and standards in construction will specify appropriate aggregate sizes for various applications, including shotcrete, ensuring a safe and durable outcome for construction projects.

In the context of shotcrete, a maximum size of 19 mm provides an optimal combination of ease of application, structural integrity, and performance.