Practical Application of Petit-Truss Bridge Girders in Modern China—The Example of the Chinese Eastern Railway Bridge Group

The Petit truss is a widely utilized steel truss design for bridges, particularly prominent on the Chinese Eastern Railway since 1900. It represents a pioneering approach in the application of transitional structures in modern Chinese bridge design, offering an innovative solution for large-span bridges, despite the technological limitations of the era. This study examines the static calculations of the Petit truss and identifies several key features: vertical loads are evenly distributed via secondary strut ties in the conventional system, and the incorporation of secondary chords helps to balance the compression and tension chords under vertical loads. The study of these bridges significantly contributed to the advancement of bridge engineering in modern China and underscored the transfer of advanced bridge technologies from Europe and the United States.