The world first three-tower-cable-stayed bridge, the Menghua Dongting Lake Mega Railway Bridge, officially finished its bridge pavement construction using ultra high performance concrete on May 12th, 2018. It is said that the flexural strength of the so-used concrete was three times of conventional concrete. Additionally, its shrinkage was reduced by 50%, and stayed intact after 700 cycles of freezing-and-thawing. The concrete was thus called as “never cracking” concrete.

Figure 1. A worker is installing shear studs on the surface of railway bridge.

“We have developed the low-shrinkage ultra high performance concrete, as well as the paving technique combining steel deck and concrete.” said Tianliang Wang, the associate chief engineer of China Railway Major Bridge Engineering Group, “The new technology of combined bridge deck has been used throughout the Menghua Dongting Lake Mega Railway Bridge, with the dual function of loading structure and water-proof layer.

Figure 2. A worker operates concrete proportioning in control room.

Compared with conventional concrete, the low-shrinkage ultra high performance concrete has multiple advantages including ultra high mechanical properties, excellent durability and volume stability, and outstanding workability. It improves concrete structures by making it lighter, thinner, and easier to construct and maintain. The full life cycle cost will also be greatly reduced.

Figure 3. The self compacting low-shrinkage ultra high performance concrete is being poured on site.

“The construction procedure is to remove rust from steel deck, install the shear stud, apply corrosion resistant material on the surface, install the reinforcing web, and pour the 50 mm thick concrete at last.” introduced Luyi Chen, the project manager of the pavement division of the bridge project.

Figure 4. The Menghua Dongting Lake Mega Railway Bridge.

“The technology of combined bridge deck was first used in the year of 2016 on the Shele Bridge in Taiyuan. After that the technology has performed well in the repair and renovation projects of various kinds of bridges.” said Qixian Tian, the chief manager of China Railway Bridge Science Research Institute, “The current project is significant in two ways. It uses the combined bridge deck of steel and ultra high performance concrete, first time ever in railway deck project in China. The overall paving area has reached 24 thousand square meters. After successfully finishing this project, we look forward to the extensive application the new technology in the near future.”