DL : E&C was awarded the contract for Namhae-Yeosu Undersea Tunnel based on the creative differentiation of design.

DL E&C was awarded the contract for Namhae-Yeosu Undersea Tunnel based on the creative differentiation of design.

2023. 12. 08

Location map of Namhae-Yeosu Undersea Tunnel

DL E&C was awarded the contract for 'Construction Project for Seo-myeon Namhae - Shindeok Yeosu National Road Project" (hereinafter 'Construction Project for Namhae-Yeosu Undersea Tunnel Project) based on its creative differentiation of design called the 'Undersea Divergence Tunnel'. DL E&C, having successfully built Korea's longest suspension bridge, 'Yi Sun-Shin Bridge', and the world's largest suspension bridge, Canakkale Bridge in Türkiye, is recognized for its technical prowess. DL E&C's winning this project demonstrates once again its challenging spirit that continuously overcomes technological limitations based on differentiation of design.

DL E&C announced on the May 22nd, 2023 that it has received a notice of the selection of a qualified company for working design of 'Construction Project for Namhae-Yeosu Undersea Tunnel' placed an bidded by MoLIT. This project is to build a new 4-lane national road with a total length of 8.09km connecting Shindeok-dong, Yeosu-si, Jellanam-do and Seo-myeon, Namhae-gun, Gyeongsangnam-do. The total project budget is KRW697.4 billion and the project includes the undersea branch tunnel section (5.76km-long). Upon completion in 20 31, it is expected that the travel time between Namhae and Yeosu will be drastically reduced from 1 hour 30 minutes to 10 minutes.

▣ DL E&C proposed a branch tunnel based on its creative differentiation of design, taking account of balanced regional development. DL E&C was the only bidder who proposed a differentiated design plan to build a new connection road to the north of Namhae-gun, in addition to the main line of the tunnel, and received the highest technical score.

The master plan for this project was a southbound unidirectional route connecting Shindeok-dong, Yeosu-si, Jeollanam-do to Seosang-ri, Namhae-gun, Gyeongsangnam-do, which has excellent tourism resources. However, DL E&C proposed a design plan that connects Namsang-ri in the northwest of Namhae, in order to solve the activation of local economy and balanced development plan at the same time. Combining the branch tunnel technology and knowhow accumulated through the experiences in constructing the Marina Coastal Expressway in Singapore and Sinwol-Yeouido Underpass (Seoul-Jemulpo Tunnel), both the southern and northern sides of Namhae can be connected to Yeosu-si, enabling tourism and local economy to be activated equally.

DL E&C also expanded tunneling shield at least double in size from 4 to 8 by means of the design of the submarine branch tunnel. As tunneling shields are increased, the construction period can be shortened by about 13 months at the same time, which reduces the construction period by about 13 months. As more tunnels are connected, the performance of evacuation, rescue and smoke exhaustion is also doubled in the event of an emergency.

▣ Applied smart construction technology to ensure optimal route feasibility and safety DL E&C applied various smart construction technologies to the Namhae-Yeosu undersea tunnel design. DL E&C made a differentiated design plan from the 'BIM (Building Information Modeling) Tunnel Design Package' developed by itself. DL E&C precisely analyzed the subsea ground conditions using AI-based Generative Design, searched for the optimal linear combination, and automatically carried out tunnel blasting design using BIM and geographic information system data. This realized the shortest construction section of the undersea tunnel out of designs submitted for bidding, and derived a creative design plan connecting both the southern and northern sides of Namhae using the project budget saved therefrom.

In particular, DL E&C applies Korea's first insulation and fire-resistant concrete independently developed by it, in order to enhance the fireproof performance of the undersea tunnel, and to prevent dew condensation. The application of the high-performance concrete, which reduces thermal conductivity by 40% compared to conventional concrete, maximized the safety of the structure.

In addition, DL E&C proposed various digital technologies to ensure safety, including the utilization of a 24-hour integrated control and safety platform, a cutting-edge technology convergence smart measurement system, and smart construction equipment, which resulted in winning an order for this project.

▣ The undersea tunnel market opened in and out of the country… "DL E&C's unrivaled technology will result in obtaining more projects" The industry expects that the undersea tunnel market in and out of the country will expand significantly in the future as the tunnel construction technology has recently improved, making the undersea tunnels more competitive in terms of cost compared to the bridges. In fact, a number of projects are underway in Korea, including 'Boryeong Undersea Tunnel opened in 2021, 'Aphae-Hwawon Undersea Tunnel, and Pohang-Yeongil Bay Undersea Tunnel. Opportunities, including "Korea-Japan Undersea Tunnel" and "Korea-China Undersea Tunnel", are expected to open up in the future.

As DL E&C has demonstrated its differentiated design and construction technologies for the undersea tunnels from winning projects for Namhae-Yeosu Undersea Tunnel, DL E&C is looking forward to obtaining more orders with its overwhelming competitiveness in the domestic and overseas undersea tunnel markets.

Mr. Kwon, the Chief Executive of Civil Business Division at DL E&C, said, "We will make every effort to pursue national and regional development and improve the quality of life of the people based on our differentiated technologies.