Noise reduction measures to be implemented on all Beijing's new subways

Noise reduction measures have been adopted on nearly half of the Subway Line 4 which will open to traffic soon, adding a further 100 million yuan to the original budget for Line 4. The Deputy General Manager of Beijing Track Traffic Construction & Management Company Ding Shukui recently said in an interview that new and advanced vibration absorption and noise reduction technology will be implemented on over 330 kilometers of Beijing’s future subway lines in order to minimize the subway’s impact on residents.

Nearly half of Line 4 implements noise reduction technology

Reporters learned that Line 4, which is over 28 kilometers in length, has been equipped with vibration absorption and noise reduction technology on nearly half of its total length. Not only is Line 4 China’s first urban rail transit to adopt comprehensive vibration absorption technology, but also the line with the largest investment in and the longest length of vibration absorption and noise reduction.

Line 4 mainly runs through Beijing’s urban districts, passing nearly 30 sites including the National Library of China, Peking University and the Former Residence of Tan Sitong among others, all of which are highly sensitive to vibration and have high requirements for noise reduction.

Noise reduction technology is implemented on six sections of Line 4

Ding said that a total of six types of vibration absorption and noise reduction technology have been used on Line 4. Of these, the world’s most advanced ladder-shaped sleeper technology was used to the largest extent, up to eight kilometers in length and accounting for 60 percent of the sections equipped with vibration absorption and noise reduction technology. This technology has been installed on six major sections of Line 4, including South Beijing Railway Station to Taoran Park section, Lingjing Hutong to Xisi section, Xisi to Xinjiekou section, Old Summer Palace to Xiyuan section, and Beigongmen to Anheqiao Bei section.

New technology can lower noise by 20 dB

Reporters learned that prior to the adoption of vibration absorption and noise reduction measures, vibration and noise on Beijing Subway Line 1 could reach 83 dB, causing noticeable vibrations of items like cups and vases on tables in residential buildings when trains pass by, while the rumbling from the underground can be heard in the evening. Residents complain that although the Lines 5 and 10 currently in service have taken measures such as installing dampers and soundproofing boards, vibrations can be felt by residents living at some sections along these lines. “The ladder-shaped sleeper technology once underwent testing on a section of Line 5, with trains’ noise reduction by 15 to 20 dB,” said Ding.

Ding added that by 2015, Beijing will have constructed a rail transit network with a total length of 561 kilometers. Aside from the 228 kilometers of subway lines currently or soon-to-be in service, over 330 kilometers of the future subway lines to be built by 2015 will be equipped with vibration absorption and noise reduction technology.

Translated by LOTO