Water Stop Wall "Hexa Gate Plug"

【HEXA TIMES】No.1 The Hexa Gate Plug (hereinafter referred to as HGP) has been adopted for the construction of the No. 3 rainwater discharge pipe of the Tachiaigawa main line ordered by the Tokyo Metropolitan Bureau of Sewerage (Contractor: Shimizu Corporation). In May 2021, this HGP was installed in the Hamagawa main line and is being used as a measure to prevent rainwater inflow when removing the temporary wall at the connection point with the Second Samezu main line. Since the tunnel cross-section is not circular but has a special shape, a pressurized tube seal type was adopted for the water stop mechanism instead of the conventional rubber ring type (Hexa Plug type). Additionally, considering the safety of the workers, it is equipped with a highly operable watertight door. There have been several heavy rain events since the installation, but the sealing performance has been good, ensuring safety within the tunnel, and the construction has been completed successfully.