Bridging Bangladesh

Built over one of the largest rivers of the world, Padma Bridge in Bangladesh is the country’s longest bridge to date spanning 3.82 miles (6.15 kilometers). In addition to its monsoon-defying, seismic-resilient and scour-tolerant design, the bridge has greatly enhanced connectivity between the country’s southwestern region and the capital city of Dhaka since its opening in June 2022, reducing travel time significantly and increasing economic opportunities for the 21 districts of the country’s southwest region.

Enhancing connectivity and opportunities

The iconic bridge features a two-level road and heavy (freight) railway design as the railway on the lower deck connects to the Trans-Asian Railway Route, enabling cargo movement between India and the container ports on the southern coast of Bangladesh. On the upper deck, the bridge greatly improves travel time between the regions separated by the Padma River as previously ferry trips across the river could take up to 24 hours due to long lines at the stations and delays brought about by fog, extreme river currents and other weather conditions. The delays in the transport of people and goods can result in rotten produce and other economic and social setbacks.

Designing for nature’s challenges

Designing the Padma Bridge was a complex task as it presented daunting challenges, particularly the increasing threat of monsoons, deep riverbed scour, and seismic activities. Dr. Robin Sham, director of global long span and specialty bridges, and our Hong Kong team applied the art and science of modern bridge technology to create this highly innovative landmark bridge.

The advanced disaster prevention and mitigation solutions applied included driving tubular steel raking piles measuring 9.8 feet in diameter (3 meters) and 400 feet long (122 meters) into the riverbed to mitigate loss of pile embedment around the bridge foundation due to deep scour from strong river currents, especially during monsoon seasons. These are the longest and deepest marine pilings among all bridges in the world.

Friction pendulum bearings were installed between the superstructure and the pier tops to allow for movements during an earthquake to relieve build-up of forces and reduce the impact of earthquakes on the bridge.

Increasing resilience into the future

With its completion, the Padma Bridge is expected to help increase the region’s annual gross domestic product (GDP) by 2.5 percent and Bangladesh’s overall GDP by more than 1.3 percent.

The innovative design of the Padma Bridge will not only ensure that it will withstand the forces of nature for many years to come, but it will also strengthen the economic and social ties of the regions separated by the mighty Padma River.