Box Jacking Tunnels
Box Jacking is a tunnelling method that involves the jacking of rectangular reinforced cement concrete (RCC) sections into the ground. The practice is commonly used in highway construction as well as in trenchless operations including constructing culverts under road and rail embankments.
Precast reinforced concrete box sections are jacked horizontally through the ground using high capacity hydraulic jacks. Only that portion of the earth that the jacked box will occupy is excavated. This method does not require any intermediate ground support, and since it is built away from the roadway, shoring or traffic control is also not necessary.
As a trenchless construction method, Box Jacking offers the advantage of minimal disruption while the tunnelling is underway.