An 847-meter-long, sound-absorbing tunnel on the high-speed railway linking Beijing and the Xiongan New Area in north China's Hebei Province, has been completed. This will help avoid the noise emanating from trains and tracks, engineers with China Railway Group Limited said.

With increasing additions of transportation hubs and railway lines across the country, train noise mitigation is of concern to people, and the newly-built tunnel seems one of the best solutions. According to its developers, the tunnel is equivalent to a sound barrier, and can minimize the noise generated by bullet trains traveling at a speed of 350 kph, the fastest commercial train service in the world.

Built on a railway bridge, the tunnel has a design life of 100 years. Its main structure adopts a round, steel frame. The external surfaces of the tunnel are covered by sound-absorbing metal panels with a total area of 22,000 square meters, said chief engineer Zhang Tengfei.

To ensure the project quality, workers also conducted 4 million fatigue tests, which are equivalent to simulating 40,000 trains passing per year, for 100 years.