Abstract: With the high-quality development of urban economy and environment, as the important element of urban transportation, the appearance design of bridges is more modern. The steel structure bridges with beautiful spatial bending and torsion structures are favored, which poses higher standard requirements and technical challenges for the design, fabrication and lean construction of complex bridges. Manufacturing and lean construction present higher standards and technical challenges. This paper takes the fully digital construction of the Xin Shougang bridge, the world's first example of a cable-stayed steel system bridge with bending and torsional steel towers, as the research object. Through the systematic research and application of key technologies of digital design, green intelligent construction and precise measurement and control, the refined and parametric collaborative design of steel tower segments and main beams has been realized which based on the modeling idea of “skeleton+template”. Segments are characterized by non-uniformly inclined spatial torsion and beams are characterized by variable section. The high-precision manufacturing of bridge components and the high-precision stress-free erection of steel tower segments are ensured through technologies such as adjustable parameters, virtual pre-assembly, and 3D laser scanning.

Key words: digital design, green construction, precise measurement and control, space bending-torsional steel bridge