American Truss Bridge Connections in the 19th Century. II: 1850-1900

Following the introduction of iron in the 1840s, bridge companies came to dominate bridge procurement. Their designs featured proprietary compressive elements and joint details. As analysis of statically determinate trusses evolved into an ordinary skill, statically indeterminate forms and prestressing fell into disuse. The statically determinate “American pinned truss” with built-up compressive elements and eyebars became the mainstream design. American fabricators produce ductile eyebars with extraordinary dimensional accuracy. However, all-riveted lattice trusses, principally designed by New York Central Railroad engineers, provided competition. In general, such designs performed satisfactorily and helped to calibrate approximate design procedures for riveted joints. The development of shop and field riveting equipment finally made riveted, gusset-plate connections practical by the turn of the century.