WUHAN, Nov. 15 (Xinhua) -- Construction of a double-deck suspension bridge with the longest span in the world is expected to be completed in October 2019, said an engineer working on the project.

The bridge, with a 1,700-meter-long main span across the Yangtze River in Wuhan, central China's Hubei Province, saw the first steal beam installed for the bridge deck Thursday.

The main structure of the bridge deck consists of 49 steel beams that are each 36 meters long, 32.5 meters wide and 10 meters tall. Each beam weighs around 1,000 tonnes, the weight of about 200 adult elephants.

Liang Xianwei, an engineer with the project, said the project is expected to be finished in October next year.

After completion, the bridge will have two decks of six-lane roads and is expected to ease traffic, Liang said.