Korea Construction of the Gimpo-Paju Expressway 2

Summary

This project involves the construction of a road tunnel crossing beneath the Han Riverbed. With the largest diameter in South Korea at 14 meters, the project utilizes a massive Shield TBM (Tunnel Boring Machine)&mdash;measuring 125 meters in total length (including the main body and auxiliary equipment) and weighing 3,200 tons&mdash;to excavate an approximately 2.98 km section, 20 to 35 meters below the surface of the Han River. It serves as the core segment of Section 2 of the Capital Region Second Ring Expressway (Expressway Route 400), connecting Gimpo and Paju.<br /> By applying the large-diameter Slurry Pressure Balance (SPB) Shield TBM method, the excavation safely navigates the challenging conditions beneath the Han River, which are characterized by shallow overburden (the depth from the tunnel crown to the ground surface), high water pressure, and complex mixed ground. It is widely recognized as a highly demanding project that represents the pinnacle of South Korea&#39;s large-diameter underwater tunneling technology.