The Yuanjiang Railway Bridge, which has the tallest bridge pier in the world and the longest span between two piers, and is part of the Chinese section of the 925.5-kilometer China-Laos railway, has got a major boost after builders finished installing 18 out of the 56 steel truss complexes forming the bridge.

The 832.2-meter-long railway bridge, which spans the Yuanjiang River with four piers in between and two platforms at both ends, is considered one of the difficult projects on the China-Laos railway, a major undertaking in the Belt and Road Initiative.

“We are now heading to the highest pier and hope to reach it before the end of October this year,” said Zhou Jihong, a project manager from the China Railway No 4 Engineering Group Co Ltd (CREC4), the company building it.

The main span of Yuanjiang Railway Bridge is 249 meters in length while its No 3 pier is 154 meters high, about the height of 54 stories in a high-rise, said Zhou.

The foundations of the tallest pier go 78 meters underground and took 22 months to build, and can withstand a weight of more than 150,000 metric tons even without the passing of the trains, said Chen Changguo, deputy Party secretary of the Fifth Division of CREC4 which participated in the project.

The dual-track bridge, spanning the V-shaped Honghe River Canyon in Southwest China’s Yunnan province, is one of 134 bridges being built on the 508.5-km Chinese section of the railway, which links Yuxi city in Yunnan and the Lao capital Vientiane and will be fully operational in December 2021.

According to Chen, construction of the Chinese section, also called the Yuxi-Mohan Railway, began in April 2016 with an investment of 51.6 billion yuan ($7.9 billion) and 86.12 percent of it is comprised of bridges and tunnels, joining the Mohan-Boten border gate in northern Laos.

The 417-km-long Lao section, linking Mohan-Boten and Vientiane, has an operating speed of 160 km per hour with an investment of 37.4 billion yuan, said Kang Ning, the publicity chief for the Fifth Division of CREC4.

As a demonstration project in China’s “going global” strategy for its high-speed railways, the China-Laos railway is an achievement in Sino-Lao cooperation under the BRI, she said, adding that they will also try to make it into an important channel for China to better connect with the outside world for economic and cultural exchanges.

“China aims to build a 5,500-km Trans-Asia Railway, which begins in Yunnan’s provincial capital Kunming and travels through Laos, Myanmar, Thailand, Vietnam, Cambodia and Malaysia, before ending in Singapore,” said Ding He, a deputy project manager for the railway project who is also from CREC4.

Earlier, China and Thailand started building Thailand’s first high-speed railway in December 2017, which will link to the China-Laos railway, Ding said.

Bai Yunxia, a deputy director from the Qiaotou Community of Honghe Street at Yuanjiang Hani, Yi and Dai autonomous county, said her community of 3,347 people are hoping that the railway would start operations soon so as to make transportation more convenient and the local economy more prosperous.