쌍용건설

Ssangyong (Chairman S. Joon Kim) has announced that it completed the Express Bus Terminal Station for Seoul Subway Section 913 on May 6, an endeavor that is generally considered the most difficult project ever in Korea’s subway construction history. The new subway line will be launched in July.

The completed Section 913 entailed the construction of a 1,270 meter-long railway between Sehwa Girls’ Middle and High School and the Express Bus Terminal in Seocho-gu, Seoul, as well as two subway stations. The project involved intensely challenging work, since it required the construction of a new subway station under the underground shopping mall at the Express Bus Terminal in an area packed with large buildings and stores along the street, including Shinsegae Department Store, the Marriott Hotel, Central City, and the Express Bus Terminal.

The station is designed as a venue for passenger transfers from three different subway lines, including Lines 3, 7 and 9. Accordingly, Ssangyong used a Tubular Roof construction Method (TRcM), and Cellular Arch Method (CAM) together for the first time in the world, as it was impossible to use common techniques such as open tunneling or a shield method.

The project was the most difficult such work conducted in the history of Korea’s subway construction, as the constructed section passed just 15 centimeters below the existing Subway Line 3. It was a turnkey project that required the company to conduct design and construction work simultaneously.

To conduct the project, a Ssangyong technology team made inspection tours to various subway stations in Europe, and paid special attention to the Venezia Subway Station, which has similar conditions to the Express Bus Terminal Station but has a different ground. Accordingly, the company employed for the first time in Korea the CAM that had been adopted at Venezia Subway Station, and used TRcM according to the conditions of the site, employing two different engineering methods for the first time in the world.

Ssangyong secured four underground work spaces through TRcM, and, for the first time in the world, constructed and linked a large-diameter tunnel using CAM, opening a new chapter in subway construction technology and engineering. Additionally, the company used the tunneling method for a 730-meter section, and the NATM tunneling method for a 885-meter section, thus employing all kinds of techniques to carry out the project. (refer to the construction proceeding diagram)

The project involved huge construction costs as well, since it was implemented with various cutting-edge engineering methods. As much as 48 percent of the entire budget was spent on constructing the subway station sections (220 meters), with construction costs amounting to an average 500 million won per one meter-long section. All told, the project for Section 913 alone cost 180 billion won, a budgetary record.

Meanwhile, more than 40 internationally recognized tunnel experts, including those from France, Belgium, Switzerland, the Netherlands and Japan, visited the Subway Line 9 site, which had emerged as a nerve center of new engineering techniques, in April 2006, when construction work was well underway, enabling Ssangyong to earn global recognition for its outstanding construction technology. The experts, who were attending the ITA WTC 2006, voiced their acclaim and praise as they toured the site of the Express Bus Terminal project, which was being constructed by deploying state-of-the-art techniques beneath an area packed with high-rise buildings.

The Station won the Seoul Metropolitan Infrastructure Headquarters’ award as a “Beautiful Station” in March, along with the “Civil Engineering Structure of the Year Award” presented by the Korea Society of Civil Engineers, demonstrated not only technological excellence but also artistic merit. Ssangyong has now completed landmark subway stations that are considered among the most beautiful in the Seoul subway system. These include the recently completed Express Bus Terminal Station, and Subway Line 6’s Noksapyeong Station (winner of the 2001 Seoul Metropolitan City Construction Award), which has become a popular venue for wedding ceremonies and diverse cultural activities thanks to its beautiful environs. Built as Korea’s first large tunnel-style subway station, Noksapyeong Station, and now the Express Bus Terminal Station, are considered the most challenging projects in the history of Seoul subway construction.

Ssangyong, which ranks among the top echelons of Korean builders in civil engineering, now has a track record of constructing a subway line extending more than 30 km in total, and continues to remain Korea’s undisputed leader in subway construction projects.