Southwest China’s concrete bridge breaks 600-meter-long arch span, setting a world record and surpassing other bridge-building countries such as Japan
The Tian'e Longtan Bridge over the Hongshui River, situated in Tian'e county in Hechi, South China's Guangxi Zhuang Autonomous Region File photo: VCGA bridge in South China's Guangxi Zhuang Autonomous Region has shattered the world record for concrete arch bridges, with the main span jumping from 445 meters to 600 meters in one leap, surpassing achievements made by other bridge-building countries such as Japan and Croatia, Chinese news portal stdaily.com reported on Wednesday.The "key technologies for 600-meter-class concrete arch bridge construction" project, centered on the Tian'e Longtan Bridge, which spans 600 meters over the Hongshui River in Guangxi, grabbed the top prize at a provincial science and technology awards ceremony on August 24.The Tian'e Longtan Bridge over the Hongshui River, situated in Tian'e county in Hechi, Guangxi, is a two-way four-lane bridge with a total length of 2,488.55 meters. It is the world's longest steel-reinforced concrete arch bridge in terms of span, according to Xinhua News Agency. It opened to traffic in 2024.For decades, Japan, Croatia and other bridge‑building powers published studies on 600-meter concrete arches, but projects in those countries never got past 390 meters.According to stdaily.com, engineers working on the bridge greatly reduced its weight. In a long-span concrete arch, the bridge's own dead load accounts for over 90 percent of the total stress - and the concrete wrapped around the steel skeleton alone makes up more than half of that.To lighten the load, the design team split the main arch into two separate ribs and removed the less‑stressed middle sections, narrowing the total width from 23 to 13 meters. That cut the concrete volume from 40,000 to 28,000 cubic meters - a 22 percent reduction per meter compared with 400-meter-class bridges - while keeping the stress level essentially the same.Engineers also made innovations in concrete pouring to eliminate cracking.Arch bridge is an important type of modern bridge. It was once believed in the industry that conventional concrete arch bridges could hardly exceed 400 meters in span, and that concrete‑filled steel tube arch bridges often struggle to surpass 500 meters in arch length. Tian'e Longtan Bridge has broken through the industry‑recognized 600‑meter‑class technical barrier.Compared with a cable‑stayed bridge alternative, the Tian'e Longtan Bridge saved 110 million yuan ($16.37 million) in construction costs, and maintenance over its 100‑year design life is expected to be 470 million yuan less. In 2023, during its construction, the International Association for Bridge and Structural Engineering and the Chinese Academy of Engineering held a global conference in Nanning, the provincial capital of Guangxi, where experts hailed the bridge's technology as "world‑class," according to the report.Global Times
