Explaining the size of the 10.3 km long bridge over the Yangtze River in Jiangsu province that opened to the public Sept. 11, Chinese media compared it to building a bridge over the Mississippi River. The bridge reduces travel time between the cities of Changzhou and Taizhou from one hour to 20 minutes.

Record bridges over the Yangtze have been a major part of China's infrastructure buildout in recent decades. Six of the ten longest cable-stayed bridges in the world are over the Yangtze and were built in the last 20 years.

Unusual Asymmetrical Design

The bridge's lower deck features a regular railway line, a subway line and a regular road in one structure. 

The bridge designers chose not to use a standard design of having the rail alignment along the center of the bridge in between the road lanes. Given that the rail sections weigh up to three times as much as the road, having it off-center caused some problems. Uneven loading of the support cables was identified is one. A team led by Qin Shunquan, chief scientist of the China Railway Group, had to adjust the cable tensions on the bridge’s railway side to keep the deck level.

But this fix to the cables in turn shifted the structure itself, misaligning its centerline. That problem was resolved by calibrating the shape of each prefabricated bridge segment during production, allowing the deck to naturally straighten out once assembled, official sources said.

“We split the problem into two parts and solved them separately. That’s how we cracked the challenge of building the world’s first asymmetrical large-span bridge." Shunquan told state broadcaster, CCTV.

The decision to not locate the railway alignment in the middle of the bridge with each direction of traffic on either side was driven by other concerns, he said. “That set-up creates major inconveniences,” since when lanes are split, emergency vehicles cannot easily around to reach an accident, Shunquan explained.

The Mighty Yangtze

Strong river currents also presented a challenge. "The bridge foundation has been reinforced for extra strength to withstand the currents,”said Li Zhen, project on-site chief for the Jiangsu transport department.

Two 350-m-tall, diamond-shaped reinforced concrete and steel towers support the cables. The project team used what it calls the world’s first intelligent tower crane for precise placements. With a lifting capacity exceeding 10,000 metric tons, the deck crane is equipped for millimeter-level precision in placing ultra-heavy segments.

There were also other intelligent machines on the site. “During operations, the team employed the latest intelligent robots for the first time. These robots could navigate complex underwater terrains and clean sand from the caisson's corners,” Zhen said.

Crews installed 80 permanent sensors to track micrometer-level structural shifts during multimodal traffic. The bridge is designed to withstand natural disasters such as earthquakes and typhoons, ensuring its safety and reliability under extreme conditions, official sources said. It also incorporates intelligent monitoring systems to provide real-time data, allowing for proactive maintenance and ensuring long-term safety.

“By introducing large-scale automated production equipment clusters, 3D laser-scanning inspection systems, intelligent manufacturing processes and micro-innovations, we successfully overcame the high-standard quality control challenges of large bridges." said Ma Zenggang, project manager at China Railway Baoji Bridge Group, another project team team.