The world's largest diameter mud shield machine under construction rolled off
Beijing, May 20 (Youth.cn) - The world's largest diameter mud shield machine "Mountain and River" under construction rolled off in Jinan, Shandong province on May 19th. With 17.5 meters of diameter, the mud shield machine will be used to build the Chuanhuang Tunnel on Huanggang Road in Jinan city. Photo/VCG
Editor:He Chang