Los Angeles River Bridges: North Main Street Bridge

The Los Angeles River currently flows east for about 40 miles along the north side of the Santa Monica Mountains and then turns south for another 40 miles until it empties into San Pedro Bay. As the river approaches downtown Los Angeles it's crossed by ten old arch bridges.

I was hoping that since today is Cesar Chavez's birthday, I would be able to discuss the bridge that bears his name. However, the next bridge downstream is North Main Street, a reinforced concrete deck arch built in 1910 by Carl Leonhardt and H.G. Parker. It is a three span, open spandrel arch, 300 ft (91 m) long and 56 ft (17 m) wide. It's in an industrial area with railway tracks and transmission towers on both sides of the river. The bridge has two pier walls in the river with large cutwaters to protect it during floods. It would be interesting (but maybe dangerous) to see this river running full. The bridge has been here for 100 years, so apparently the cutwaters are doing a good job.

Los Angeles River Bridges: North Main Street Bridge by Mark Yashinsky is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 3.0 United States License.

Los Angeles River Bridges: North Spring Street Bridge

After spending two weeks looking at arch bridges across the Thames, we are moving to Los Angeles to look at their river crossings. Although the Los Angeles River is often dry and has a concrete liner for much of its length, it is a tidal river just like the Thames, at least near its mouth in Long Beach. Like the Thames, the Los Angeles River poses a flood hazard to its residents because it cannot carry all the water from the river basin during long heavy rains. Although Los Angeles is far younger than London, it has some well-designed, older arch bridges in the downtown area.

We looked at the Broadway Bridge (just north of this bridge) on February 19th. It's the most northern of the arch river crossings (except for the Hyperion Bridge in Glendale) and was built in 1910.

In 1874 the Downey Avenue Bridge (named after the governor) was built at this site. It was replaced in 1928 by the current North Spring Street Bridge. It is a long viaduct crossing over railroad tracks and city streets and includes a two-span, open spandrel, deck-arch across the Los Angeles River. It was strengthened in 1939, got a seismic retrofit in 1992, and was undamaged during the 1994 Northridge earthquake.

The bridge is 682 ft (208 m) long, 40 ft (12 m) wide, and each arch span is 146 ft (45 m) long.

The North Spring Street Bridge isn't as handsome as North Broadway. The approaches are girder spans instead of arches like on North Broadway. The arch ribs are separate instead of continuous and there aren't any architectural details.

Note the huge cutwaters they put on both sides of the pier to protect it from debris that can be carried during floods. These walls provide a convenient location to paint graffiti as shown in the photo (you can see the North Broadway Bridge behind North Spring Street in the photo).

More information on the Los Angeles River can be found at http://folar.org/

More information about the North Spring Street Bridge is at http://bridgehunter.com/ca/los-angeles/53C0859/

Los Angeles River Bridges: North Spring Street Bridge by Mark Yashinsky is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 3.0 United States License.

Thames River Bridges: Southwark Bridge

By now, we can see that most of the Thames crossings are steel or iron deck arches. Southwark Bridge is just downstream from the two Blackfriar Bridges. In fact, its five steel arches are aligned with nearby bridges to prevent crosscurrents from occurring with the tides.

The current Southwark Bridge was designed by Ernest Lamb and Basil Mott and completed in 1921. The architect (Ernest George) provided viewing platforms above the piers and cruciform lampposts along the baluster. This is an example of a bridge becoming less attractive due to the architect's contributions.  Starlings were provided on both sides of the bridge as the current can flow in both directions.

The bridge is 800 ft (244 m) long, 55 ft (17 m) wide, and its owned and maintained by the City of London. It was given protected status in 1995.

Along the Thames Walk on the south bank are pictures of the bridge construction and a tunnel under the bridge approach shows frost fairs that occurred at this location. Occasionally, the Thames would freeze over and various entertainments would be provided. There are no thoroughfares or nearby train stations adjacent to this bridge and so it carries fewer vehicles or pedestrians than other Thames crossings. In fact, the owners of the original bridge at this site (a toll bridge designed by John Rennie in 1819) ended up going bankrupt.

Thames River Bridges: Southwark Bridge by Mark Yashinsky is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 3.0 United States License.

Thames River Bridges: Blackfriars Railway Bridge

Blackfriars Railway Bridge was built in 1864 for the London, Chatham, and Dover Railway. After the formation of the Southern Railway in 1924, the Waterloo Railway Station became the chief hub and this bridge fell into disuse. In 1985, the bridge's superstructure was removed.

St Paul's Railway Bridge was built next to Blackfriars Railway Bridge in 1886. It is a five-span, wrought-iron, deck-arch designed by John Wolfe-Barry and Henri Marc Brunel.

When St Paul's Station was renamed Blackfriars in 1937, the new bridge became the Blackfriars Railway Bridge.

The existing piers of the old Blackfriars Bridge are eventually going to be used to support an extension of Blackfriars station across the Thames.

Thames River Bridges: Blackfriars Railway Bridge by Mark Yashinsky is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 3.0 United States License.

Thames River Bridges: Blackfriars Bridge

Just east of Waterloo is Blackfriars Bridge. It is a five span, wrought-iron deck arch; 923 ft long (280 m) and widened (in 1910) to its present 105 ft (32 m) width. The piers have decorative columns carved with freshwater fauna upstream and saltwater fauna downstream to represent the tides flowing under the bridge.

The bridge was designed by Thomas Cubitt, built by P.A. Thom & Co., and owned by the City of London. It was opened in 1869 by Queen Victoria and named after the nearby Blackfriars Railway Station. Blackfiars Bridge carries both vehicular and pedestrian traffic.

These old steel and iron bridges used to be painted a uniform dull gray, but in recent years, they have received careful painting which makes them much more attractive.  The expense of a large maintenance staff is paid back by having handsome bridges that are protected from the deterioration that quickly destroyed previous Thames crossings.

Thames River Bridges: Blackfriars Bridge by Mark Yashinsky is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 3.0 United States License.

Thames River Bridges: Waterloo Bridge

We'll skip the Hungerford and Golden Jubilee Bridges in order to study the next arch bridge along the Thames.

The Waterloo Bridge is at a bend in the River Thames, providing great views of London. It has a clean, modern appearance partly because there was no money (during  WWII) for ornamentation on the bridge. In fact, this bridge was damaged (and repaired) due to air raids during the war. The bridge was named after the location of the English (and Prussian) victory over Napoleon in 1815.

 The Waterloo Bridge is a five span reinforced concrete deck arch faced with Portland limestone. It is 1230 ft (375 m) long, 80 ft (25 m) wide, and with 230 ft (70 m) long arch spans. The piers have an interesting shape that mimics the shape of the arches.  The bridge was designed by Giles Gilbert, opened in 1942, and became a protected bridge in 1981.

On the south bank is the Festival Concert Hall, the Museum of the Moving Image, and the National Theater. On the north bank is Covent Garden and The Strand. The Waterloo Bridge is an attractive structure in an attractive area of London.

Thames River Bridges: Waterloo Bridge by Mark Yashinsky is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 3.0 United States License.

Thames River Bridges: Westminster Bridge

The first Westminster Bridge was built in 1750.  The tidal flow is particularly strong in this area, and scour became a problem. It was exacerbated when the old London Bridge (downstream) was replaced in the 1820's.

The current Westminster Bridge was designed by Thomas Page and opened in 1862. It is 252 m (826.8 ft) long and a 26 m (85 ft) wide. This is the only seven-arch wrought iron bridge across the Thames.  It has architectural detailing by Charles Barry who designed the nearby Palace of Westminster. The bridge is painted green to match the seats of the House of Commons.

Thames River Bridges: Westminster Bridge by Mark Yashinsky is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 3.0 United States License.

Thames River Bridges: Lambeth Bridge

It's half a mile north of Vauxhall to the Lambeth Bridge in central London. The demand for a bridge at this location diminished after Westminster Bridge was built. However, Westminster's capacity was eventually exceeded and the first Lambeth Bridge (a suspension structure) was built in 1862. Although it was originally able to carry 800 tons, it slowly deteriorated and was closed to vehicles by the beginning of World War I.

The current Lambeth Bridge (a five span steel deck arch) was designed by George Humphreys in 1929 and completed in 1932.  It was painted red to match the color of the benches on the nearby House of Lords. However, this was the first bridge built by the London County Council, representing a new, more democratic London.

Thames River Bridges: Lambeth Bridge by Mark Yashinsky is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 3.0 United States License.

Thames River Bridges: Vauxhall Bridge

At Vauxhall, there is evidence of bridges crossing the Thames for the last 3500 years.

The current Vauxhall bridge replaced an 1816 iron bridge that was too narrow and eventually had too many structural problems to warrant repair. The new bridge (designed by Alexander Binnie and completed in 1906) is five steel deck arches supported on granite piers and abutments.

This bridge has distinctively painted arches and balustrades (mustard and ketchup colored) and giant bronze statues of women standing on the piers representing human achievements (farming, architecture, etc). The bridge is 246 m (809 ft) long and 24 m (80 ft) wide. It was declared a protected structure in 2008.

The Tyburn and Effra Rivers used to empty into the Thames at Vauxhall Bridge, but there is little evidence of them today (they flow underground in pipes). There was a penitentiary on the north bank that was demolished in 1867.  The Vauxhall Gardens entertained visitors from the the 16th to the 19th centuries. Today, the headquarters for M16 sits on the south bank and the Tate Britain Museum and the Chelsea College of Arts sit on the north bank.

Thames River Bridges: Vauxhall Bridge by Mark Yashinsky is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 3.0 United States License.

Thames River Bridges: Grosvenor Bridge

The next arch structure downstream from Battersea Bridge is the Grosvenor Railway Bridge.  It is now three bridges as more tracks were gradually added. The bridges were constructed from 1858 to 1866.  They were substantially rebuilt using new, steel members in the 1960's. Today the bridges are 284 m (832 ft) long, 54 m (177 ft) wide, and with the longest span being 53 m (175 ft).

Trains on the Southern Railway line from Brighton to Victoria took 50 minutes in the 1950's. Today, due to increased congestion, the trip takes much longer. The bridge is just west of the Battersea Power Plant.

Thames River Bridges: Grosvenor Bridge by Mark Yashinsky is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 3.0 United States License.

Thames River Bridges: Battersea Bridge

I'm missing  photos of Putney Bridge (a five span, masonry deck arch), Wandsworth Bridge (a haunched steel girder), and Cremorne Bridge ( a five span, steel deck arch) so we'll go to the next arch bridge downstream, which is the Battersea Bridge.

Like most Thames crossings, the present bridge replaced an earlier timber structure built in 1771. It was immortalized in paintings by J. M. W. Turner and J. M. Whistler. The old bridge was bought by the Metropolitan Board of Works (MWB), who promptly replaced it in 1890 with a new structure designed by Joseph Bazalgette.

The river has become broader as we've moved downstream, and so this bridge required five arch spans to cross the river. Granite piers and abutments support cast-iron arch ribs braced with wrought-iron cross-members. The bridge is painted green, with golden inset decorations, an intricate ballustrade, and tall lamp posts supporting three lights. It is 413 ft (126 m) long and 55 ft (17 m) wide and carries vehicles and pedestrians.

This is an interesting area of London. Roman weaponry was found when the banks for the first bridge were being excavated.  'Battersea' comes from the name of an ancient chief who resided here, perhaps 1500 years ago when the Thames was a marshland.  Later, the marsh was drained and this area became rich farmland. In the 19th century Cremorne Gardens was built and provided entertainment where a power station now stands.

The bridge was designated a protected structure in 1983. In 2005 a barge became stuck under one of the arches and damaged the bridge. It was closed for several months while repairs were made.  

Thames River Bridges: Battersea Bridge by Mark Yashinsky is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 3.0 United States License.

Thames River Bridges: Barnes Railway Bridges

Around a bend in the river from Chiswick Bridge are the two Barnes Railway Bridges. The first bridge is a steel deck arch designed by Joseph Locke in 1849 (who also designed the Richmond Railway Bridge). Concerns about the bridge's safety prompted the London and South Western Railway to build a three span steel bowstring arch beside it in 1895.  The existing stone piers were widened, steel arch segments were shop fabricated, brought to the bridge site by barge, lifted, and placed onto the piers.

This bridge has two sets of tracks as well as pedestrian walkways.  It is one of the few railway bridges on the Thames that allows for foot traffic. In fact, the walkways were strengthened to support all the people who crowd onto them to watch the Oxford and Cambridge Boat Race in March. The race begins downstream at Putney Bridge and ends upstream just before the Chiswick Bridge. Racing along this bend in the river is considered challenging because of the changing winds and currents.

This is a pleasant part of the Thames, surrounded by elegant 18th and 19th century mansions, the Duke's Meadows, and a nature preserve. It is hard to imagine that just fifty years ago it was so polluted that it was considered a dead river.

Thames River Bridges: Barnes Railway Bridge by Mark Yashinsky is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 3.0 United States License.

Thames River Bridges: Chiswick Bridge

One is barely aware of crossing over Chiswick Bridge while driving on busy A316. However, approaching the bridge along the River Thames is a much more pleasant experience.

I was surprised by the number of rowers along this stretch of the river.  We passed several pubs that boasted of their rowing teams, which must be a British institution.

The Chiswick Bridge is just a bend in the river (about a mile) downstream from Kew Bridge. The total length is 185 m and comprises five reinforced concrete arch spans clad in Portland limestone.  It was designed by Alfred Dryland and built in 1933 by Sir Herbert Baker.  It  was dedicated  by the Prince of Wales (who later became the Duke of Windsor after abdicating the throne).

We can see that 20th century arch bridges across the Thames (strengthened with reinforced concrete) have shallower and longer spans. However, the use of stone cladding and ornamentation makes the Chiswick and Kew Bridges look like older bridges. Maybe it's because arch bridges have been used for so many centuries that we expect them to reflect an older architectural style.

Thames River Bridges: Chiswick Bridge by Mark Yashinsky is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 3.0 United States License.

Thames River Bridges: Kew Bridge

The River Thames has a tidal fluctuation of several meters at Kew Bridge.  This photo must have been taken at low tide as the banks and starlings are quite evident.  We were on a visit to the Royal Botanical Gardens, whose entrance is a few meters from the bridge. This photo (looking north) doesn't do justice to the idyllic setting of Kew Green and Kew Garden on the south bank.

This is the third bridge built at this site. The first two bridges were toll crossings, built by the owner of the ferry crossing (and his son) during the 18th century but they proved to be inadequate.

The third bridge was better funded (£250,000) by Middlesex and Surrey Counties. It was built of white limestone quarried from the Isle of Purbeck in Dorset County.  It is a 360 m (1182 ft) viaduct that includes a three-span, closed spandrel, stone masonry arch over the River Thames. Two of the piers are in the river and support an arch span of 41 m (133 ft).

The bridge was completed in 1903 to much fanfare including a visit from King Edward VII.  It was declared a protected structure in 1983.

Thames River Bridges: Kew Bridge by Mark Yashinsky is licensed under a Creative Commons Attribution 3.0 United States License.

Thames River Bridges: Richmond Railway Bridge

The River Thames flows northward in a series of curves between Richmond and Kew.  About a mile downstream from the Richmond Bridge are three handsome arch bridges. Unfortunately, I don't have a very good photo of them.

The Richmond Railway Bridge was originally designed by Joseph Locke in 1848 as three 100 ft (33 m) long arch spans built of six cast-iron ribs. Concerns about its structural integrity prompted the London and Windsor, Staines, and South-Western Railway (L&SWR) to ask the Horsley Bridge Company to replace the structure in 1906. Mr. Jacomb-Hood, the chief engineer of the L&SWR used the old piers and abutments but designed new steel arches and a new deck.  This bridge was completed in 1908. The girders and deck were replaced in 1984 and it was declared a protected structure in 2008.

Just downstream from the railway bridge is the 1933 Twickenham Bridge, composed of three reinforced concrete arches clad in stone.  As previously mentioned, this bridge was built to reduce traffic demand on the Richmond Bridge. It has been reported that the piers are supported on compressed cork. This bridge was also declared a protected structure in 2008.

By clicking on the photo, you should be able to see these two structures in the distance.

A third structure, an arch footbridge a little further downstream, was built in 1894 to dam the Thames River during low tide.  Under the footbridge are steel dams that can be drawn up to allow river traffic during high tides. During low tide the dams are lowered to hold back the water that otherwise would turn this section of the Thames into a narrow stream.

Thames River Bridges: Richmond Railway Bridge by Mark Yashinsky is licensed under a Creative Commons Attribution 3.0 United States License.

Thames River Bridges: Richmond Bridge

The River Thames is 346 km (215 miles) long from Gloucestershire to the North Sea.  It is a tidal river from the Thames Estuary to Teddington. Upstream of Teddington, the river is controlled by sluice gates at a series of weirs.  It is thought that people have lived along the Thames since the Neolithic period (about 10,000 BC).

The Richmond Bridge is a couple of miles downstream from the locks at Teddington.  It has been captured by many artists including in three paintings by J. M. W. Turner.

It was built in 1777, making it the oldest surviving bridge on the Thames (it was widened in 1937).  It is a five span, closed spandrel stone masonry arch bridge.  It is 90 m (300 ft) long and varies between 7 m (24 ft) and 11 m (36 ft) in width.  When the bridge was widened, the stones were carefully removed, stored, and put back on the widened bridge. Since the bridge is still rather narrow, most of the traffic takes the nearby Twickenham Bridge (built in 1933) onto a busier thoroughfare and sparing the old town of Richmond.

Thames River Bridges: Richmond Bridge by Mark Yashinsky is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 3.0 United States License.

Singapore's Bridges: Elgin Bridge

The first bridge to cross the Singapore River was built at this spot in 1819. It linked the Chinese community on the south side of the river to the Indian merchants on the north, and so the roads on each side were called South Bridge Road and North Bridge Road. The street names have remained the same but the bridge has been replaced several times.

The current Elgin Bridge is a tied arch bridge that was built in 1929. It is 46 m (151 ft) long and 25 m (82 ft) wide. It carries the name of the Governor of India at the time that the previous bridge was built at this site (in 1862).  Like the Anderson and Crawford Bridges, it is supported by three concrete arches with heavily reinforced concrete hangers supporting the floor beams and the deck.  Like the Anderson Bridge, there are two traffic lanes between each pair of arches and pedestrian walkways outside of the arches. However, because the Anderson Bridge is near the mouth of the river it is considerably longer than the Elgin Bridge.

Simple concrete cross-framing members provide lateral stability between the arches. Handsome cast-iron lamps are supported on pedestals at the ends of the arches (taken from the previous bridge at this site). Below the lamps are bronze plaques showing a lion striding in front of a royal palm. This is what Sang Nila Utama, the founder of Singapore in 1299, said that he saw when he first landed on the island.

The bridge was refurbished in 1989 and selected for conservation in 2008.

Singapore's Bridges: Elgin Bridge by Mark Yashinsky is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 3.0 United States License.

Singapore's Bridges: Anderson Bridge

We're going to travel up the Singapore River to study a couple of lovely old arch bridges.

The Anderson Bridge was built in 1910 to carry the traffic that was overloading the Cavenagh Bridge (see February 7th), just as the Esplanade Bridge was built in 1997 to carry some of the traffic that the Anderson Bridge could no longer handle.

By now we should be able to recognize the Anderson bridge as a steel tied arch. In fact, we can see the heavy steel tie under the bridge deck.

This bridge has many beautiful details. The pedestrian railing is supported laterally by graceful steel members resting on concrete floor beams decorated with stars. Instead of the cables and concrete hangers we've recently seen supporting the deck, this bridge has large built-up steel members for hangers and slender diagonal members on both sides of the arch.

The bridge is 70 m (230 ft) long and 28 m (92 ft) wide.  There are three arch ribs, with two lanes of traffic between each pair of arches and a pedestrian walkway on the outside of the arches.  The decorative cross-bracing above the arch ribs carry lanterns and there are two masonry arches at each end of the bridge.

Singapore has done a wonderful job of preserving this elegant bridge.  

Singapore's Bridges: Anderson Bridge by Mark Yashinsky is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 3.0 United States License.

Singapore's Bridges: Esplanade Bridge

About two km south of the Crawford Bridge, where the Singapore River pours into Marina Bay, is the Esplanade Bridge. It is a seven span open spandrel arch, 260 m (850 ft) long, 70 m (230 ft) wide, and with eight traffic lanes and two walkways. It is a popular tourist destination, close to museums and theaters, and with excellent views of Marina Bay. On National Day and New Year's Eve the bridge is closed to traffic to allow pedestrians to watch the fireworks displays from the deck of the bridge.

The bridge was completed in 1997 by the Obayashi Corporation but I couldn't find out who designed it. It appears to be more of a folded shell structure rather than a typical arch bridge.  The arch spans are about 35 m (115 ft) long with only about a 2.5 m (8 ft) rise and the deck is unsupported over the piers.  It is an unusual design but a very attractive bridge.

Singapore's Bridges: Esplanade Bridge by Mark Yashinsky is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 3.0 United States License.

Singapore's Bridges: Crawford Bridge

For the last week we've been looking at arch bridges in Toronto. We're going to continue exploring arch bridges, but we're changing our location to the city-state of Singapore.

Actually, Toronto and Singapore are similar. They both were ruled by Great Britain, they both have a very diverse population, and they are both comfortable and attractive cities with many handsome bridges.

The Crawford Bridge crosses the Rochor River just upstream from its mouth in the Kallang Basin. The Kallang Basin and the Singapore River flow into Marina Channel. More information on Singapore's rivers is at Thinkquest.

Like the other bridges we've recently studied, the Crawford Bridge is a reinforced concrete through arch, in which the deck is a tie that pulls on the ends of the arch like the string of a bow. Also, like those other bridges, there is no cross-bracing and instead of having cables to support the deck it has concrete hangers.  There is a 15 page report about the reconstruction of this bridge by Thomas Christie Hood in a 1929 journal article of the Institution of Civil Engineers.

As shown on the photo above, the Crawford Bridge is wider than it is long. It has three arch ribs and includes pedestrian walkways and eight traffic lanes in two directions.  It is in the Little India and Arab Quarter, about a mile northeast of downtown Singapore.

Singapore's Bridges: Crawford Bridge by Mark Yashinsky is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 3.0 United States License.

Toronto's Bridges: Charles Sauriol Bridge

We'll finish our exploration of arch bridges in Toronto with a look at another reinforced concrete through arch. The Charles Sauriol Bridge is similar to yesterday's Pottery Road Bridge, except the concrete hangers aren't flared, there's a sidewalk extending outside of the arch, and the ends of the arch are protected with short, decorative walls.

This bridge carries drivers across the Don River to the parking lot for the Charles Sauriol Conservation Reserve. It also carries bicyclists across the river and back onto the Don River Bike Trail. The trail is about 14 km in length from Lake Ontario to Edwards Gardens and goes over and under a variety of interesting bridges. More information on the trail can be obtained at: http://www.ontariobikepaths.com/DonRiver.htm

Toronto's Bridges: Charles Sauriol Bridge by Mark Yashinsky is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 3.0 License.

Toronto's Bridges: Pottery Road Bridge

In the 19th and early 20th centuries, the farming communities north of Lake Ontario needed to cross the Lower Don River and many bridges were built.

The Pottery Road Bridge is a reinforced concrete horseshoe arch that was built in 1928. A parallel girder bridge was built in 1977 to carry northbound traffic. The original bridge was renovated in 1988.

This is a through arch, but with the deck supported by reinforced concrete hangers instead of with steel cables.  

More information on bridges crossing the Lower Don River can be obtained at: http://www.lostrivers.ca/points/ravinesbridges.htm

Toronto's Bridges: Pottery Road Bridge by Mark Yashinsky is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 3.0 United States License.

Toronto's Bridges: Dundas Street Bridge

We are continuing down the Don River in Toronto to our next bridge. It's another three span crossing, but with a steel deck arch only for the center span over the river.  This bridge is not quite as elegant as the last few bridges we've been studying, but it still seems quite serviceable. Its main problem is that its old and poorly maintained. The concrete pier on the right has long vertical cracks, suggesting that the reinforcement is rusted, expanding, and causing the concrete to split.  In fact a lot of the concrete that should be on the piers appears to have spalled and fallen onto the ground. I read that the city of Toronto planned to do some repairs and hopefully it's now in better shape.

However, the steel members look in good repair (freshly painted and no rust). In fact, the steel members looks beefier than the Gerard Street Bridge, with deeper arch ribs and with stiffer cross-bracing between the spandrel columns. Since both the Gerard and Dundas Bridges are four lane bridges carrying streetcars, the Dundas Bridge may have been designed more conservatively simply because it is an older design.

Toronto's Bridges: Dundas Street Bridge by Mark Yashinsky is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 3.0 United States License.

Toronto's Bridges: Gerard Street Bridge

We are continuing south on the Don River in Toronto, past the Riverdale Park Bridge to a three-span steel, deck arch; the Gerard Street Bridge. This is a nicely designed structure. The three pinned arches are clearly articulated at the piers and at midspan.  The concrete piers support the deck and the arches through openings in the piers. Even the lampposts are nicely designed on concrete bases on the outside of the barrier rail.  

These bridges not only span the Don River but Don Valley Parkway and Bayview Avenue, requiring three long spans. This makes steel deck arch spans a good solution, as long as the abutments can resist the longitudinal force from the arches.

Toronto's Bridges: Gerard Street Bridge by Mark Yashinsky is licensed under a Creative Commons Attribution 3.0 United States License.

Toronto's Bridges: Riverdale Park Bridge

This is a pedestrian bridge that links the east and west sides of Riverdale Park across the Don River in Toronto. It is a viaduct that includes a steel deck arch for the river crossing.

The arch is a clean and elegant design. There are no spandrel columns and the arch transitions into the steel girders rather than sitting below them.  You can see stiffeners radiating out from where the arch joins the steel girders.

Toronto's Bridges: Riverdale Park Bridge by Mark Yashinsky is licensed under a Creative Commons Attribution 3.0 United States License.