.png){kind=logo}
Newsletter N°88 - April 2026
🏗️ Construction: China’s First 3D-Printed Integrated Tunnel Lining Passes Inspection
On April 26, China’s first 3D-printed integrated tunnel lining demonstration project, constructed by China Railway Seventh Group at the Xiangqian Tunnel of the Guangzhou-Zhanjiang High-speed Railway, successfully passed on-site inspection. This milestone marks a critical leap for architectural 3D printing from above-ground to underground applications in complex environments.
The project, part of a national "14th Five-Year Plan" research initiative, achieved breakthroughs in design, materials, and equipment. The integrated 3D-printed tunnel lining structure utilizes sprayed 3D-printing high-strength and toughened fiber-reinforced concrete. By implementing a suite of advanced methodologies—including multi-stage homogeneous dispersion, multi-frequency vibration, anti-sagging and mechanical toughness assessments, as well as anti-permeability and anti-cracking optimization—the project has successfully refined the design of high-performance fiber-reinforced materials.
This integrated design-construction and support-waterproofing system fundamentally overcomes traditional bottlenecks, such as high operational risks and limited structural integrity in extreme environments. Moving away from conventional "experience-dependent" methods, this innovation shifts tunnel construction toward an "intelligent control" model.