Between East and West: Poland's Pioneering BridgesIN DISCUSSIONS of the history of civil engineering, the role of Poland is sometimes overlooked. In the United States, Poland's best-known contribution to the field is probably Ralph Modjeslci, M.ASCE, the accomplished Polish-American bridge engineer But Poland has also produced several groundbreaking bridges of its own, including the first iron bridge on the European mainland, the first welded roadway bridge in the world, and continenta1 Europe's first long-span lattice truss bridge, the Old Wisla Bridge, which ASCE honored in 2004 in its Historic Civil Engineering Landmark Program.
Poland's earliest bridge of note was the Sigismund Augustus Bridge, which predated the Industrial Revolution. Named for Sigismund 11 Augustus, who as king of Poland commissioned it, the wooden structure stretched 500 m across the Vistula River in Warsaw. Not only was it the first permanent crossing of the Vistula in that city; it was also the longest wooden bridge in Europe at the time of its completion (1573). In addition to its 18 fixed spans, it had a movable section that made it possible for the river to remain open to navigation. In 1603, however, an ice floe destroyed the structure. More than 260 years wou1d pass before Warsaw residents wou1d see another permanent bridge across the Vistula.
Smaller, but just as significant, was a single-span bridge erected in 1796 over the Strzegomka River in Lazany, (see follow-on posting) a village southwest of Wroclaw, Poland, in a region that then belonged to Prussia. John Baildon, the Scottish engineer who designed it, had come to Prussia three years earlier at the invitation of Count Friedrich Wilhelm von Reden to modernize the regions ironworks. Niclas August Wilhelm von Burghaus commissioned the project and requested an iron structure that wou1d represent the state of the art.
The world's first iron bridge had been erected in Britain in Coalbrookdale in 1779, and others had followed in that country and in the United States, but Baildons was the first in continental Europe. The nearly 6 m wide structure featured five parallel arch girders, each approximately 17 m long and 3 m high, supporting an iron deck paved with stone and flanked by decorative railings. The span was destroyed during World War 11, but segments have been recovered and preserved.
Yet another groundbreaking crossing, the Maurzyce Bridge, was erected on the Slidwia River near Lowicz, Poland, in 1929. The unassuming steel structure consists of two main truss beams supporting a single span that is 27 m long and 6.8 m wide; the parabolic top chord of each truss reaches a modest height of 4.3 in at midspan. The bridges significance 1ies not
in its frame, however, but in how it was constructed. Designed by Stefan Bryla, a professor and welding pioneer, it was the first welded steel road bridge in the world. Though it is no longer in service, it stands today near its original site as a monument to Bryla's ingenuity.
From the perspective of the history of civil engineering, Poland's most important crossing predates Bryla. It is the Old Wista Bridge, also called the Tczew Bridge or Lisewski Bridge, which crosses the Vistula in the town of Tczew. Its tubular form resembles that of the better known first Britannia Bridge, which stood astride the Menai Strait in Britain from its
construction, in 1850, until its destruction by fire 20 years 1ater. Like the Britannia, the Old Wisla made a unique contribution to the development of long meta1 spans.
The bridges origin can be traced to the 1840s, when the Prussian government moved to bind its eastern territories more closely to Berlin by establishing the Prussian Eastern Railway, which eventually stretched from that city to
Koenigsberg (now Kaliningrad, Russia). The widest river on the route - and the greatest obstacle to the railway - was the
Vistula, which flows through Tczew on its way to the Baltic Sea.
The engineer responsib1e for designing and building bridges for the railway was Carl Lentze, a high-ranking government officia1. Lentze bad seen Thomas Telford's Menai Suspension Bridge on a study trip to Britain and planned to build a suspension bridge of his own at Tczew. By 1847 he had arranged for the supply of materials, employed hundreds of workers, and established a brickworks and iron foundry on-site, but a financial crisis brought the project to a halt. During the lull, Lentze cook a second trip abroad, and this one inspired him to build an entirely different kind of bridge.
Lentze visited several British bridges, but he was especiat1y interested in Robert Stephenson's Britannia Bridge, which was then under construction on the Menai Strait. To convey two railroad tracks 46l m across the strait while maintaining the necessary structural stiffness, Stephenson and his colleagues William Fairburn, Eaton Hodgkin son, and Edwin Clark had devised an intriguing alternative to a suspension bridge: a four-span structure featuring tubes of wrought iron rectangular in cross section and large enough for trains to pass through. Each of the bridges two 140 m main spans and two additional 70 m spans consisted of a pair of tubes, one for each track. Riveted plates of wrought iron and paired angles made up the walls of the tubes.
Upon his return, Lentze discarded his plans for a suspension bridge at Tczew and went to work designing a structure similar to the Britannia Bridge but with one major difference: the walls of the tube would consist not of iron plates but of a lattice of diagonal members crisscrossing between two parallel chords. The result would be a lighter structure with reduced wind drag.
If Lentze design was inspired by the Britannia Bridge, it also owed much to the work of the American architect and engineer Ithiel Town, who patented a lattice truss bridge design in 1820 and 1835. The Town lattice truss became a popular structural form in the United States, especially for wooden covered bridges. The Irish engineer John MacNeill is credited with introducing iron lattice bridges in Britain. Lentze had visited one of MacNeill's bridges, a 43 m iron lattice span completed in 1845 over the Royal Canal in Dublin.
Lentzes bridge dwarfed MacNeill's. Its six spans of wrought iron, each 131 m long, gave it a total length of 786 m (837 m if the monumental porta1s are included), making it one of the longest bridges in Europe at that time. But the credit does not belong co Lentze alone. Rudolph Eduard Schinz, a Swiss civil engineer performed the structural analysis and the detailed design, modeling every two spans as a single continuous beam. Friedrich August Stueler, a Prussian architect, conceived the monumental portals and the paired towers atop the masonry piers. Steuler even crowned the towers with battlements, as if he knew the bridge wou1d twice be engulfed by war.
While working on the Tczew project, Lentze, Schinz, and Stueler constructed a similar bridge over the Nogat River at Ma1bork, Poland, also for the Prussian Eastern Railway. The Nogat crossing was based on the same structural principles as the Old Wisla Bridge but consisted of just two lattice truss spans of wrought iron, each 103 m long.
The construction of the Old Wisla Bridge resumed in 1850, and King Frederick William IV of Prussia himself
came to Tczew for the ceremonial laying of the cornerstone on July 27, 1851. The work proceeded smoothly for all except Schinz, who in 1855 died of a stroke that was attributed to overwork. But even those who were there to witness the bridges opening on October 12, 1857, refrained from organizing a grand celebration because of a cholera outbreak.
The Old Wisla Bridge quickly became a model for other lattice truss crossings throughout Europe. Notable examples - none of them extant - include a bridge over the Kinzig River in Offenburg, Germany (1858); the Cathedral Bridge on the Rhine in Koeln (Cologne), Germany (1859); another Rhine bridge at Kehl, Germany (1861); and the Kierbedzia Bridge, which spanned the Vistula in Warsaw (1864).
Railway planners expected trains to use the Old Wista Bridge infrequently at first. They even installed wooden planks on the deck so that horse-drawn carriages could cross the bridge when the track was idle. Before long, however, railway traffic had increased so much that it became necessary to build a second bridge parallel to the first. When the new, double-tracked bridge opened, in 1891, the Old Wista Bridge was converted to roadway use.
The removal of railroad was the first of several major changes the bridge has undergone over the years. Between 1910 and 1912, three 82 m truss spans were added to the eastern end of the bridge in response to alterations in local flood control structures that broadened the rivers floodplain. It was in this expanded condition - the six origina1 spans plus three modern truss spans - that the bridge became a Polish possession after World War I, since the Treaty of Versailles made Tczew a part of the resurrected Poland.
Then came World War 11.
In the early morning hours of September 1, 1939, the first day of the German invasion of Poland, German soldiers launched a surprise attack on the Tzew bridges in an attempt to seize them before the Polish army bad a chance to blow them up. When the attack failed, Polish fighters partially destroyed both structures as a defensive measure,and three spans of each bridge were lost. The Germans quickly replaced the 1891 railroad bridge with one of their own. In 1945 the retreating German army destroyed the railroad bridge again but ignored the ruins of the original 1857 crossing, which survived the war.
The Old Wista Bridge today is a composite of several types of structures, each of which represents a chapter in its history. Three of its spans date back to the 1912 expansion project. Other truss spans were added to put the bridge back into service after World War 11. But the three 1857 spans that survived the war are still there, as are four of the original stone towers. These spans are the earliest remaining examples of this stage of development in the history of long-span metal bridges. The bridge as a whole, however,is in poor condition and in need of rehabilitation. Whether it will endure or meet the same fate as so many others of its type remains to be seen. JEFF L. BROWN
Jeff Brown is a contributing editor to Civil Engineering.
0CTOBER 2015 Civil Engineering [45]
(( ) a uratowane jego części planuje się wyeksponować w Otwartym Muzeum Techniki we Wrocławiu.
.jpg/440px-Kierbed%C5%BA_Bridge_(1900).jpg)
