Construction of South Asia's First Underwater Shield Tunnel Makes Key Progress

The right line of the Karnaphuli underwater tunnel in Bangladesh was completed on Oct 7, marking a breakthrough in the first underwater tunnel project in South Asia and China's first overseas large-diameter underwater shield tunnel project.

The right line of the Karnaphuli underwater tunnel in Bangladesh is dug through on Oct 7. [Photo/sasac.gov.cn]

Located at the estuary of the Karnaphuli River in Chittagong, a coastal city in Southeast Bangladesh, the Karnaphuli underwater tunnel is the first of its kind in the country to connect the east and west banks of the river.

The four-lane 9.3-kilometer tunnel has a designed speed of 80 kilometers per hour, with a shield section of 2.45 kilometers and tunnel diameter of 11.8 meters. 

A view of the construction site of the right line of the Karnaphuli underwater tunnel in Bangladesh [Photo/sasac.gov.cn]

An ultra-large-diameter tunnel boring machine developed by CCCC Tianhe Mechanical Equipment Manufacturing Co Ltd, which has a 12.12-meter diameter and weighs more than 2,200 tons, was used in the project.

The project was generally contracted by China Communications Construction Company Limited (CCCC). CCCC's China Road and Bridge Corporation and CCCC Second Harbor Engineering Company Ltd. are responsible for construction of the project.

Designed and built to Chinese standards, the project is a key part of the Bangladesh-China-India-Myanmar Economic Corridor and the Belt and Road Initiative.

Once operational, it will greatly improve traffic in Chittagong and boost economic growth in Bangladesh, as well as improve the Asian highway network to promote connectivity between Bangladesh and neighboring countries.

(Executive editor: Niu Yilin)