Shield construction technology is one of the important knowledge that municipal professionals must master. This paper will analyze the related knowledge of shield construction technology for readers from the advantages of shield construction technology, lining types and double-layer lining structure.

Advantages of shield construction

Shield construction technology shows its unique advantages in weak water-bearing stratum, areas where ground structure cannot be dismantled and construction conditions are difficult: low vibration, low noise, fast construction speed, safety and reliability. These advantages make shield method a tunnel construction method with little influence on the surrounding environment.

Lining type

There are three main types of tunnel lining constructed by shield method, including precast lining, double-layer lining combined with cast-in-place reinforced concrete integral lining and extruded concrete integral lining. Prefabricated lining, also known as segment, is a common lining form in urban rail transit tunnels, which is assembled by prefabricated components in the factory at the tail of shield.

Double lining structure

In order to prevent tunnel leakage, prevent lining corrosion, correct construction mistakes, reduce noise and vibration, and as internal decoration, we usually add integral concrete or reinforced concrete lining to the assembled lining to form a double-layer lining structure. This double-layer lining structure is adopted in the South-to-North Water Transfer Project in China.