Shotcrete Thickness Requirements for Tunnel Acceptance:

I. Shotcrete Thickness Requirements for Tunnels

During tunnel shotcrete construction, there are specific requirements for the shotcrete thickness during acceptance. Generally, the shotcrete thickness must not be lower than the design requirements. Different tunnels have different design requirements, therefore the shotcrete thickness will also vary. However, regardless of the requirements, the shotcrete thickness should meet the design requirements; otherwise, rework is necessary.

II. Uniformity of Shotcrete Thickness

In addition to meeting the design requirements, the uniformity of the shotcrete thickness is also crucial. The thickness should be even across all areas, without any localized areas that are too thick or too thin. This is a challenging aspect of tunnel shotcrete construction.

To ensure uniformity, construction personnel need to carefully control the spraying volume and speed to ensure even coverage of the tunnel walls.

III. Compaction of Shotcrete Thickness

Besides meeting the design requirements and ensuring uniformity, the compactness of the shotcrete is also important. Insufficient compactness will significantly impact tunnel safety, while excessive compactness will increase shotcrete costs.

To ensure the compactness of the shotcrete, construction personnel need to pay attention to the composition and ratio of the shotcrete and strictly follow the requirements for mixing to ensure its compactness.