At 11:20 a.m. on January 31, 2012, the steel box girders for main bridge of Nanjing 4th Yangtze River Bridge was successfully closed. Yang Weize, Standing Commissioner of Jiangsu Provincial Party Committee and Secretary of Party Committee of Nanjing, Ji Jianye, Mayor of Nanjing, Chen Jiabao, Director of Nanjing People's Congress, Miao Helin, Chairman of Nanjing People's Political Consultative Conference, and You Qingzhong, Director-General of Jiangsu Transportation Department, arrived at the bridge and extended their regards to the constructors, and hammered in the closure dowel together. Hongjun, Secretary of the Party Committee of CRBBG, and Cheng Yuhai, General Manager of Yangzhou Steel Structure Co., Ltd, were also present at the closing ceremony.

Nanjing 4th Yangtze River Bridge is one of the passages over Yangtze River in Nanjing's city layout of "Five-Bridge and One-Tunnel" approved by the State Council, and also the passage and important part of Nanjing ring expressway that belongs to the main line of Shanghai-Chengdu national road. The bridge is located at 10 km downstream from Nanjing 2nd Yangtze River Bridge, staring from Hengliang Town Liuhe District, spanning Yangtze River at Longpao Town, and ending at Qilin pivot of Shanghai-Nanjing Expressway. The main bridge is 1,418 meters long, and the total length of steel box girders is 2,189.60 meters.

Different from Nanjing 2nd and 3rd Yangtze River Bridges, the 4th bridge is the first suspension bridge in Nanjing and the twin-tower three-span suspension bridge with the greatest span in China at present. The 1,418 meters main span takes the third among the same kind of bridges in the world. The stiff girders of main bridge adopt flat and streamlined closed thin-walled steel box girders, with 3.5 meters high, 38.8 meters wide (incl.the seal), and 15.6 meters long of standard segment. The material for the main bridge is Q345D steel, and quantity of steel for the whole bridge is 34,000 tons.

CRBBG undertook the fabrication of all the 34,000 tons steel box girders. From March, 2010 and after 22 months' working, CRBBG overcame various difficulties such as time limit and heavy task, and realized the aim of safety and quality assurance and the completion of workshop fabrication in advance.

The successful closure of Nanjing 4th Yangtze River Bridge symbolizes the great phasic achievement has been reached for the bridge construction.