The bridge was designed in 1927 by Stefan Bryła, one of the pioneers of welding in civil engineering.[1] Bryła, a professor at theLwów University of Technology, conducted extensive theoretical studies on possible usage of welded steel joints in construction, as well as various aspects of oxy-fuel welding and electric arc welding. Both procedures have been known at least since late 19th century, but their application was mostly limited to house and shipbuilding. However, since the tests proved welded joints could be powerful enough to sustain large forces, in mid-1920s Bryła decided to design a welded bridge. He used his earlier design of a riveted bridge, which Bryła and Wenczesław Poniż converted to use the new construction method.However, the cross-beams and some elements of the chords were re-designed from scratch. The design was ready in 1927, and predated the construction of a similar yet shorter welded railway bridge built by Westinghouse Electric and Manufacturing in Turtle Creek, Pennsylvania (designed and built a couple of months before), which however was completed several months faster and as such was the first welded bridge in the world, regardless of a type.
The then-new technique of arc welding allowed to save the weight of the otherwise ordinary truss bridge: its overall weight is 56 metric tons, while a riveted version would have weighted over 70 tons. Apart from construction method, the construction itself is an ordinary truss bridge with two main truss beams, a straight bottom chord and a parabolic top chord. In addition to two lanes for road traffic, the bridge also included two side-walks for pedestrians.
