Discover how Q345D structural steel enables a cantilevered glass walkway to span the gorges of Tibet-and the challenges of getting it there.
Perched on a cliff in the Nujiang River Canyon, with a drop of over 130 meters, Chengdu-based architecture firm Archermit has created a stunning glass walkway whose Q345D steel truss structure follows the river below. Inspired by the 72 hairpin turns of the iconic Nujiang "72-Bend" road, the walkway extends 37 meters outward in a single cantilever, forming a similar "hairpin" shape.
The high-altitude glass viewing platform is the core structure of the project, explains Zhe Yang, partner at Archermit. "The ground is paved with high-transparency safety glass, creating a true 'sky path' in the air-transforming the thrilling driving experience of the Nujiang 72 Bends into an ultimate high-altitude walking experience." This allows visitors to deeply experience the majestic, wild beauty and breathtaking charm of the Nujiang Canyon.
Complementing and Contrasting the Rugged Landscape
Yang continues: "The exterior materials consist mainly of Tibetan-red Q355NH weathering steel plates, responding to the cultural significance of color in the region while also standing out from the surrounding environment. The highly weather-resistant steel is not only strong and durable, but its rough texture also engages in dialogue and fusion with the rugged landscape around it."
Since most of Tibet experiences over five months of snow and ice each year-and construction must proceed at high altitude with low oxygen levels-building the structure was a challenge. But relying on Q345D low-temperature toughness steel as one of the core building materials made the construction process somewhat easier.
Steel Is Ideal for Demanding Construction Conditions
"In Tibet, where transportation is inconvenient and construction is heavily affected by weather conditions, Q345D steel structures are an ideal construction method due to their minimal on-site work, rapid installation, and controllable overall costs," says Yang. "The high-altitude glass viewing platform adopts a Q345D steel truss structure, with the farthest cantilever extending 37 meters and the nearest extending 27 meters. The truss height near the cantilever support is 2.4 meters, gradually decreasing to 1.5 meters at the cantilever end, which stands over 130 meters above the Nujiang River."
The modular nature of steel structures facilitated the smooth transportation and installation of the viewing platform's structural materials. "The entire Q345D steel truss was fabricated in the factory in 46 sections, then transported to the site for assembly and lifting. The main truss of the cantilever portion was divided into 26 sections. The lifting process required extremely high precision, including pre-camber of the cantilever structure, welding control, and displacement monitoring at key points," Yang says.
"High altitude poses significant physical challenges for construction workers; for example, the Nujiang viewing platform is located at an elevation of approximately 2,800 meters, and six different waves of workers were used for pile foundation drilling alone. Many workers from low-altitude areas simply cannot adapt to the high-altitude climate, which limits the available labor pool."
High altitude also presents major challenges for certain construction processes, such as electric welding, concrete pouring, and metal panel installation. "During the project's construction, we collaborated with multiple authoritative institutions, industry experts, professors, and our construction team to overcome numerous obstacles. After six years of effort, the project was successfully completed."
Effort and perseverance certainly paid off. The Nujiang 72-Bend Canyon Scenic Area is an incredible feat of design and engineering, appearing magnificent from every angle.
Need high-altitude or corrosion-resistant steel for your project?
Jiangsu Cunrui supplies Q345D low-temperature structural steel and Q355NH weathering steel with full mill certification, modular fabrication, and export-ready packaging.