The Shanghai Tunnel Longshui South Road Cross River Tunnel has successfully used a new type of thixotropic mud for the first time

The "Longyao" shield tunneling machine started from a 38 meter deep starting shaft and proceeded uphill throughout the entire process, with a maximum slope of 4.99% and a minimum turning radius of R400m until it "drilled out" of the ground. When received, the minimum top soil cover was only 2.56 meters.

The Pudong South Line Tunnel is approximately 481 meters long. Although the length is short, the technical content is extremely high and the construction difficulty is extremely high. When carrying out ultra shallow soil cover and the entire uphill construction, it is necessary to do a good job in controlling the shield posture, stabilizing the front soil, and managing transportation vehicles.

The Shanghai Tunnel uses a new type of thixotropic mud to be injected into the outside of the shield shell through the reserved hole in the middle shield, to prevent ground settlement and reduce friction resistance during propulsion. During the turning process, a new type of thixotropic mud is injected into the back side of the turn to assist in sharp curve turning, laying a good foundation for the safe connection of the entire tunnel.

Shield tunneling is constructed under shallow and ultra shallow soil cover until the ground reaches zero soil cover and important pipelines such as rainwater well pipes are penetrated. During the construction process, a new type of thixotropic mud needs to be injected, which is convenient for injection during construction. The integration of mixing and injection is preliminarily achieved, achieving settlement control at the millimeter level during the construction phase.

Sincerely thank Shanghai Tunnel for providing us with this cooperation platform, and we look forward to further cooperation with Shanghai Tunnel in various fields of tunnel development in the future!