
NEWS AND VIEWS n n n Architect’s Approach A Tale of Two Bridges: Lessons to be Learned By Paul Sheehy, Managing Partner, Connecting Innovation aving spent 37 years in the roofing and construction busi- ness, I know how to build things to last. Over the years, I Hhave seen too many examples where the driving criteria was not longevity and durability, but rather the lowest installed cost. I’ve also had a lifelong interest in history, which gives me a distinct per- spective when examining two of Montreal’s iconic structures. Victoria Bridge, Montreal, QC, about 1875. © McCord Museum, The new Champlain Bridge over the St. Lawrence, which was MP-0000.2917 completed and opened to traffic late this summer, is an imposing ocean than any other river, aside from the Amazon. In contrast to structure. Its completion knits Montreal to the south shore by car the Amazon, the St. Lawrence freezes, creating powerful ice floes and light rail, greatly expanding the commuting area serving Great- that exert tremendous stress on any structure traversing the river. er Montreal. But it is not this new bridge I want to focus on. Rather, Only two kilometres apart, both bridges were game changers in we will discuss the old Champlain bridge it replaces and the vener- their day but were the result of very different building processes, able Victoria Bridge, which was completed in 1860, just before the practices, philosophies, and outcomes. They provide a contrast be- American Civil War. tween the two different building philosophies: quality engineering The Victoria bridge expanded Montreal’s reach, not just to the versus value engineering. south shore of the St. Lawrence, but all the way to New York City and Portland, Maine. It knit together parts of eastern Canada and VICTORIA BRIDGE linked Canada to the broader U.S. economy. Construction of the Victoria Bridge commenced in 1854, and Both bridges cross the mighty St. Lawrence River, which emp- it opened in 1859 as the longest bridge in the world, spanning al- ties the Great Lakes into the sea, carrying more fresh water to the most three kilometres. A bridge this long across a powerful river had never been done before. Considering the difficulties contract- ors faced while building the cutting-edge bridge across the frozen St. Lawrence River, it was hailed the Eighth Wonder of the World. Visitors came to Montreal from around the world to view this engin- eering marvel, and it was completed ahead of schedule to coincide with the visit of Albert Edward, Prince of Wales, the heir apparent, as part of a grand tour of Canada and the United States. Historical records provide detailed insight into what was involved with building a bridge that would set new engineering standards. Many doubted the practicality of such an audacious undertaking. The Grand Trunk Railway saw the bridge as an economic necessity to connect the Island of Montreal (at the time, the economic centre of Canada), to U.S. markets and seaports on the Atlantic. Floating derrick and pile driver, Victoria Bridge, Montreal, QC, 1859. © The bridge was designed by Robert Stephenson as a tubular McCord Museum, N-0000.193.98 2 structure. The contractors were Peto, Brassey, and Betts, and they 40 Fall 2019 • Ontario Building Envelope Council n n n NEWS AND VIEWS Victoria Jubilee Bridge, Montreal, QC, 1897. © McCord Museum, VIEW-8835 drew upon the expertise of retired engineer James Hodges, who in- sisted that only the best tradesmen in the world would be involved in the construction of the Victoria Bridge (they paid salaries high- The old Champlain Bridge (right) reaches over the construction site of the er than those offered for comparable work in Europe). The design new bridge in June 2018, showing the southern end of the bridge that spans team mandated only the best materials of the era be incorporated. the St. Lawrence River at Montreal, Quebec. The new bridge, now open, features a multi-lane expressway and commuter line. The old bridge will BACKGROUND eventually be dismantled. Photo credit: www.istockphoto.com | Ziggy3. • The original design called for only the central span to be con- structed of metal; the rest of wood. Estimated cost of construc- and beams with relative ease. The design assumed ongoing main- tion: $1,600,000. tenance, along with the replacement of structural components dur- • Hodges and his engineering team insisted that to build the ing the bridge’s lifecycle. longest bridge in the world across the St. Lawrence the installed The stability of trains crossing the St. Lawrence River in winter cost should not drive construction decisions. winds was a concern in 1859, so the bridge was essentially a wrought • The second plan submitted in 1852 advocated building with no iron tube over water. As the gauge and width of tracks improved, wood at a cost of $3,000,000, a preferred solution that was safer providing greater stability for train traffic, the tubular structure was and offered far more attractive lifecycle costs. removed. The new design featured oversized stone piers with the upper Grand Trunk Railroad expanded the bridge in the 1890s to in- portions in the shape of ice-breaker hulls, a first in bridge construc- clude a pedestrian lane on one side and a horse and buggy lane tion. Today, these piers are as effective in breaking ice as they were on the other. Both were toll lanes that were modified again for car in 1859. traffic. The construction team devised the first derricks to lift the heavy In the mid-1950s, there was significant controversy surrounding rocks from 72 barges used to erect the bridge. They also cham- the expenditure of $7 million in public funds on changes and main- pioned just-in-time delivery scheduling for prefabricated parts tenance on what some considered a soon-to-be obsolete bridge. shipped from Liverpool, England. Why? The completion of the Champlain Bridge. During its construction, Hodges refused any significant altera- tions to the design. Fortunately, Grand Trunk supported Hodges’ CHAMPLAIN BRIDGE uncompromising standards. Pressure to seek short-term savings at Construction of the Champlain Bridge, which started in 1957 the expense of long-term durability was resisted before and during and was completed in 1962, is the antithesis of the enlightened pro- construction. The final cost of the bridge was $6,600,000, a stagger- cess that resulted in the Victoria Bridge. It is a classic case of value ing sum in 1859. CONSTRUCTION FACTS • The 24 piers contain more stone than the Great Pyramid of Giza. • 144 horses and 3,040 men worked on the bridge every day. • 1,540,000 rivets for 9,004 tons of iron plates were prefabricated in England, delivered on time, and built into the structure. • The ice-breaker stone pier design is still used today by engineers around the world. The genius of the Victoria Bridge is found in almost every as- pect of its engineering, but the forward-thinking practicality of its ongoing maintenance defines its brilliance. Designed for ease of Framework of tube and staging, Victoria Bridge, Montreal, QC, 1859. © maintenance and upgrading, the bridge allows swapping of girders McCord Museum, N-0000.193.127 Pushing the Envelope Canada 41 NEWS AND VIEWS n n n So, what exactly happened? Pratley’s firm, Monsarrat & Pratley, was awarded the design contract. Their design was bid and award- ed for the imposing arched centre of the bridge and constructed as designed. The second bid called for tenders on the spans connecting the main superstructure to the Island of Montreal and the south shore; 28 bids were submitted, and the lowest bid was accepted. That design proposed pre-stressed concrete, opposing Pratley’s steel design. Pre-stressed concrete was newer technology designed by Eugène Freyssinet. When the bid for the spans was awarded to Freyssinet’s low bid, Pratley wrote in defence of the original design, calling the low bid “concocted like a piece of knitting, so there’s no way you can repair a beam. It is all too tightly tied together.” His cautionary plea that The new (left) and old Champlain bridge as construction wraps up in repair may be unfeasible proved a disastrous prophecy for Canadian summer 2019. Photo credit: www.istockphoto.com | Jonas Han. taxpayers. Freyssinet’s design met the new minimum standards; it was the engineering gone horribly wrong, triggered by dysfunctional pro- lowest bid and was deemed—within the strictest theoretical inter- curement processes. pretation of value engineering—the proper decision. The Champlain Bridge was designed by P.L. Pratley, a legend In a 2014 Montreal Gazette article, Call it a $500-Million Ban- in Canadian bridge design who was involved in the investigation of dage, the director of engineering for the Champlain Bridge states the collapse of the Quebec Bridge, which killed 75 workers in 1907. that “the bridge’s unique structure possesses the greatest challenge Pratley worked on an impressive list of world-class bridge designs for its rehabilitation. Because the bridge was built with all the beams such as the Jacques Cartier Bridge (1930) in Montreal, Quebec interconnected, it is impossible to remove one and replace it with City’s Île d’Orléans Bridge (1935), Vancouver’s Lions Gate Bridge another. So, engineers had to come up with systems to reinforce the (1938), Halifax’s Angus L. Macdonald Bridge (1955), and the Bur- bridge that have never been tried before.” He is referencing the pre- lington Skyway Bridge (1958) crossing Hamilton Harbour. stressed concrete design sections of the bridge. While working on the Champlain Bridge, Pratley died in The cost to complete the bridge as Pratley designed would have 1958.
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