China-Singapore Network, Nanning, March 20(Huang Yanmei, Li Wenxia and Tang Yu)Li Shuichang, Commander of Nandan-Tian'e Xialao Expressway Construction Command of Guangxi Communications Investment Group, introduced on the 20th.，The world's longest span arch bridge under construction in Guangxi——At present, Tian'e Longtan Bridge has completed the construction of rigid skeleton hoisting and closure and concrete pouring in the pipe.，The progress completion rate of the bridge is about 66%。The bridge is expected to open to traffic by the end of this year.。

March 20，At the China Engineering Science and Technology Forum and the Second World Conference on Construction Technology of Long-span Arch Bridges held in Nanning, Guangxi，Li Shuichang interacts through live video links.，Introduce the construction progress of Tian'e Longtan Bridge to the participants.。

Tian'e Longtan Bridge is an academician of the Chinese Academy of Engineering.、Professor Zheng Jielian, School of Civil Engineering and Architecture, Guangxi University, presided over the construction.，It is invested and constructed by Guangxi Transportation Investment Group。The bridge is located 6 kilometers upstream of Longtan Dam in Tian'e County, Hechi City, Guangxi.，It is the control project of the old expressway from Nandan to Tian'e.。

According to Li Shuichang，The total length of Tian'e Longtan Bridge is 2488.55 meters，The main bridge is a deck reinforced concrete arch bridge with a calculated span of 600m.。The span of the bridge exceeds 600 meters.，The biggest difficulty is to ensure the accuracy of arch rib segment closure.，This is equivalent to 190 meters in the air.“Thread the needle”，Realize millimeter-level precision closure。

According to introduction，In order to complete the hoisting task with high quality，Under the guidance of experts, the participating units，Strengthen scientific and technological innovation，Digital cable lifting equipment for bridges has been developed.、“Process optimization，The result is controllable”A series of equipment and construction technology, such as the optimization calculation method of the cable force of the one-time tensioning buckle.，Summarize a set of cantilever assembly technology of large-span concrete-filled steel tubular stiff skeleton in mountainous area，Control the accuracy of lifting linetype within the range of millimeter level，Ffectively sol that difficult problem of linear control of arch ring of long-span arch bridge，It provides strong technical support for the construction of long-span arch bridge.。

It is reported that，After the completion of Tian'e Longtan Bridge，Bring the world's arch bridge into the era of 600 meters，It will be branded with the mark made in China on the world's largest span record of concrete arch bridge with stiff skeleton.，Advance in construction technology and method of long-span arch bridge，It has extensive scientific research value and far-reaching social significance.。

China is a big bridge country.，Guangxi is a representative province of arch bridge design and construction.。Guangxi is a typical karst landform.，There are more mountains and less plains.，Concrete-filled steel tubular (CFST) arch bridge has excellent mechanical properties and high engineering durability，Highway in Guangxi、It has unique advantages in railway construction.。(Finished)