Successful Breakthrough of Both Tubes of Bangabandhu Sheikh Mujibur Rahman Tunnel
On October 7, 2021, with the cutter of the tunnel boring machine cutting through the wall, China Communications Construction Company Limited, the EPC Contractor, and China Road and Bridge Corporation, the Constructor, successfully achieved breakthrough of both tubes of Bangabandhu Sheikh Mujibur Rahman Tunnel, making the remarkable progress of the first overseas large-diameter underwater TBM tunnel undertaken by China.
Located at the River Mouth in Chattogram, Bangladesh, Bangabandhu Sheikh Mujibur Rahman Tunnel Project connects Chattogram City to the other side of Karnaphuli River. The total length of the Project is 9.3km, with the design speed of 80km/h and a two-tube four-lane tunnel, in which the length of tunnel shield section is 2450m while the tunnel outer diameter is 11.8m. With a diameter of 12.12 meters and a weight of 2200 tons, the CCCC self-developed and manufactured large-diameter slurry pressure balanced tunnel boring machine is used for construction of the Project. During the tunnelling of the left line, the Site Project Department has overcome many significant technical challenges such as TBM launching and receiving in the water-rich silty fine sand stratum, the attitude control of TBM in upper soft and lower hard stratum, TBM tunnelling control in silty fine sand stratum, etc. Before the tunnelling of the right line, Project Department has upgraded and reformed the shield Cutter, and achieved “Nil-replacement of shield cutter and tail brush” during the tunnel boring process.
Facing the severe COVID-19 epidemic situation in Bangladesh, the carefully organization, strict requirements, and scientific epidemic prevention of Project Department ensured the life safety of both Chinese and Bangladeshi employees in the project. Facing the difficulties such as the reduction of flights, the shortage of international shipping resources, and the increase of material prices, the Project Department made scientific arrangements and organized in advance to ensure that the labor, materials, and machines required for construction entered the site on schedule. The Project Department inaugurated the boring work of the right line on December 12, 2020 and completed the work within 10 months with zero leakage in the Tunnel. The construction progress and excellent quality of the Project have been highly praised by the Bangladeshi Employer and international Consultants.
Bangabandhu Sheikh Mujibur Rahman Tunnel Project is the first underwater Tunnel in South Asia, and also the first overseas large-diameter underwater TBM tunnel undertaken by Chinese Company. The Project is funded by Export-Import Bank of China, designed and built with Chinese Standard and Chinese machines, implemented and managed by Chinese companies, and will become a shining business card of overseas Chinese Tunnel after the completion. As the critical part of Bangladesh-China- India-Myanmar Economic Corridor, the Project is the important part for building the One Belt and One Road. The construction of the tunnel Project will greatly improve the traffic conditions in Chattogram, promote economic development of Bangladesh. It also plays an important role in improving the Asian Highway Network, strengthening the connectivity between Bangladesh and neighboring countries, and boosting the international development of Bangladesh.