Sunday, December 25, 2016

Bridges of Lyon, France: Pont Raymond Barre across the Rhone River

September 2016 (45.7327, 4.8205) Pont Raymond Barre
You might have noticed in last week's blog that there was a shiny new bridge behind the Pont Pasteur. The two bridges are joined on the right bank but are widely separated on the left bank (see Google earth photo below). In that photo we can see the Pont Pasteur and today's bridge (the Pont Raymond Barre) crossing the Rhone and next week's bridges (the Mulatiere Bridges) crossing the Saone with 'La Confluence' between them.
Bridges need to be seen in some isolation to properly admire their form. However, there is too much going on around Pont Raymond Barre. Also, a bridge should flow visually from the piers to the superstructure but on the Pont Raymond Barre that flow is interrupted. There are distracting lines on the back of the piers and a full stop between the pier and the soffit. Actually the bridge looks better from a distance (see the top photo), where the interruptions are less noticeable.
The Pont Raymond Barre was designed by the architect Alain Spielmann whose book "La Resistance de Sites" was reviewed by The Happy Pontist a few weeks ago. The Pontist does a good job of identifying the deficiencies in Spielmann's designs, which may be the result of not challenging the engineer more often.
Actually, the prettiest part of the bridge is up on the deck. The timber walking surface, red sofas, and soaring arches make for an elegant environment to wait for the shuttle.

In the photo below the Pont Pasteur is on the far right, a shuttle is waiting for passengers in the center, and the stairway to the Musee du Confluence is on far left. The approach to the Mulatiere Highway Bridge and Fourviere Hill can be seen in the distance.
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Sunday, December 18, 2016

Bridges of Lyon, France: Pont Pasteur across the Rhone River

September 2016 (45.7333, 4.8208) Pont Pasteur (with the Passerelle de las Paix and the Confluence Museum)
It is a one mile walk downstream from the Perrache Viaduct to the Pont Pasteur along the Rhone. This area, near the confluence of the Rhone and the Saone, has seen less residential development then the rest of Lyon, but plans are being made to build another bridge (the Ponts des Girondins) and also to provide more parks and other amenities for the Girondins Zac (south of the railroad), which is currently mostly industrial buildings.
A bridge was built at this spot in 1914 but it was washed away by a flood in 1918. A three span arch was built in 1923 but it was destroyed during WWII. The current bridge was built in 1950. It is a three span reinforced concrete open spandrel arch bridge (composed of three arch rings) with the arches springing from foundations at water level. The arches also have flat curves that rise only about 25 ft above the water. Consequently, there are no large ships and no movable bridges across the Rhone in Lyon, just barges and pleasure craft. The river has been dammed and there is a system of locks to allow boats to travel along the Rhone (or along adjacent ship channels) from Switzerland 500 miles south to the Mediterranean. More information for those thinking about navigating this river is available from the French Government.
The current Pont Pasteur is 195m (640 ft) long and 18m (60 ft) wide. Pedestrian undercrossings (see photo above) were built in the abutments to allow people to continue walking along the quai since the arches are too low to walk under. This bridge appears to be a favorite hangout for pigeons.
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Sunday, December 11, 2016

Bridges of Lyon, France: Perrache Viaduct across the Rhone River

September 2016 (45.7466, 4.8302) Perrache Viaduct
Continuing downstream past Pont Gallieni we arrive at Perrache Viaduct, a railroad bridge across the Rhone. The bridge was named after the nearby train station (and surrounding district), whose enormous yard can be seen in the Google earth photo in last week's blog. The bridge (and the station) were built in 1856. It is a five span cast iron arch bridge on pile foundations that have been repaired, widened, and strengthened several times. It was bombed twice (by the Allies and then by the Germans) during WWII but it was only partially damaged. After the liberation the U.S. Army used the bridge to carry convoys of heavy vehicles eastward after the retreating German Army.
When looking at the bridge, it isn't hard to identify the newer and older members. The exterior arch on the upstream face (above) appears to be riveted and it supports the deck with steel spandrel columns. The exterior arch on the downstream face (below) is reinforced concrete for two of the spans (as part of a later widening or repair) perhaps because steel was hard to obtain. All of the railroad bridges in this part of France have overhead lines to power the trains.
This is the second railroad bridge that we've studied (we looked at the Viaduc SNCF for the first posting on Lyon). We'll look at several more railroad bridges as we complete our circumnavigation of Lyon and head into the surrounding countryside. I noticed a blog on how to take a train from the Perrache Viaduct to the Millau Viaduct (6 hours and $84) in case anyone is interested. Other trains go to Paris and Rome.
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Sunday, December 4, 2016

Bridges of Lyon, France: Pont Gallieni across the Rhone River

September 2016 (45.7483, 4.8320) Pont Gallieni
The first bridge that was built at this site was part of a plan in 1847 to provide a continuous route through Lyon with bridges across the Saone and Rhone. The current bridge on this east-west route is a three span steel I-girder structure that was built in 1965. The Pont Gallieni was named after a 19th century French military officer, Joseph Gallieni. An earlier bridge was named Pont du Midi but that was changed to Gallieni at his passing in 1916.
In the Google earth photo above we can see the Saone and the Rhone with an elaborate transportation system on the Presqu'ile, the peninsula between the bridges. The highway bridges are to the north and the railroad bridges are to the south. The Pont Gallieni lost two of its traffic lanes to a tram system in 2001.
 The Pont Gallieni has seven steel girders with straight girders on the approach spans and haunched girders on the center span. The girders sit on nicely tapered stone piers. I think stone is Lyon's favorite building material. Exposed stone is used for a walking surface and walls on the quays and no matter what the age of the bridge, it seems to have stone piers and abutments.
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Sunday, November 27, 2016

Bridges of Lyon, France: Pont de l'Universite across the Rhone River

September 2016 (45.7569, 4.8382) Pont de l'Universite
Continuing past the Rhone Nautical Center we arrived at the Pont de l'Universite, a three span metal arch bridge. University buildings were constructed between 1876 and 1898 on the right bank and this bridge was built to replace the ferry service and allow students to walk to class. According to the Structurae Website, the bridge was designed by Fabreque, Hinnovait, and Jean Resal and built by the Society des Forges de Franche-Comte. At it's inauguration in 1903 it was named Pont des Faculties, but it was quickly renamed the Pont de l'University.

In September of 1944, 22 bridges in Lyon including the Pont de l'Universite were blown up by the Wehrmacht. Photos of the destruction were taken by the Dusson family and are now available on the Instants Lyonnais Website. A temporary wooden bridge was built beside the damaged Pont de l'Universite while it was being repaired and it was reopened in 1947.
The Pont de l'Universite is 268 meters (880 ft) long and 20 meters (66 ft) wide.  Each span is composed of eight built-up truss arch ribs made of wrought iron from the town of Longwy. The arches are supported on piers and abutments built from stones of Porcieu-Amblagnieu.
The Pont de l'University is highly ornamented with bright red insignias of the Republique Francaise along with a laurel leaf on the piers and with shields and fleur de lis on the arch ribs. The portion of the arch above the quay is a favorite place for exercise. I saw the man in the photo below doing pull-ups from the arch ribs.
Looking to the west (in the photo below) we see the Basilica of Notre Dame Fourviere up on a hill in Vieux Lyon several miles away. This 19th century church has an eclectic architectural style different from the traditional Gothic architecture of the other churches in Lyon. 
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Sunday, November 20, 2016

Bridges of Lyon, France: Pont de la Guilotiere across the Rhone River

September 2016 (45.7569, 4.8382) Pont de Guilotiere
A bridge has been at this site since at least the Middle Ages. Oak piles were found at this location in the 1980s when they were building the subway. Arches from the bridge (shown below) were discovered on the left bank 100 meters from the current bridge, suggesting the river has changed its course over the years and explaining why the Place du Pont is located at some distance from the river.
Guilotiere refers to a nearby town that was incorporated into Lyon in 1852. At that time the bridge provided passage over the river on a direct road to Italy and so many artists and merchants moved into the area and it also became the residence of waves of emigrants seeking a better life.
The current Pont de Guilotiere was built in 1953 after the previous bridge was destroyed by the retreating German Army at the end of WWII. 
The superstructure is composed of three steel boxes connected with cross bracing and steel I-girders for the top deck. It sits on stone piers and abutments, perhaps from the earlier bridge. However, the current bridge is much wider, so the new substructure must have been reassembled from old stone.
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Sunday, November 13, 2016

Bridges of Lyon, France: Pont Wilson across the Rhone River

September 2016 (45.7600, 4.8394) Pont Wilson
About 1/4 mile downstream from the Pont Lafayette is the Pont Wilson. The city of Lyon seems to really like the United States, or at least those people who helped France during its wars, such as President Wilson who intervened to help end WWI.
The Pont Wilson replaced an old dilapidated suspension bridge in 1918 (at the end of the war). This 98 year old, four span open spandrel arch structure was considered revolutionary at the time because a reinforced concrete deck was supported on traditional Villete stone masonry arches and caissons.
Unlike many of the bridges across the Rhone, the Pont Wilson has roads (Rue Childebert to the east and Rue Servant to the west) that continue beyond the bridge. The new bridge is much wider than the suspension bridge it replaced (20m instead of 7m) with two lanes (traveling west on a one-way street) and with wide sidewalks (4.5m instead of 1.1m).
Like most of the other roadway bridges that we've studied over the Rhone, the Pont Wilson is composed of two separate arches tied together by a steel frame that supports the deck. Also like the other bridges across the Rhone the Pont Wilson was bombed by the retreating Germans and eventually rebuilt in 1948.
The Pont Wilson has dolphins to protect the bridge on both sides (both upstream and downstream). This bridge requires four spans to cross the river, while the previously studied arch bridges crossed over the Rhone on three arch spans.
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Sunday, November 6, 2016

Bridges of Lyon, France: Pont Lafayette across the Rhone River

September 2016 (45.7636, 4.8397) Pont Lafayette
Continuing downstream past the Passerelle du College is a second Rhone River crossing that survived WWII (although the center span was destroyed and rebuilt in 1946). A second bomb was found under the bridge in 2014.
The Pont Lafayette was named after a military hero in France and in the United States who was instrumental in winning the American War of Independence. With George Washington he laid siege to General Cornwallis' troops in Yorktown and forced his surrender. In 1829 Lafayette crossed the Rhone (on an earlier bridge at this site) and it was renamed in his honor. At his death the U.S. government brought soil from Yorktown to place on his grave.
The current Pont Lafayette was built in 1890 to replace an aged structure. It's a three span metal arch. The stone piers are decorated with sculptures representing the Rhone and Saone Rivers (reproductions of sculptures found at the Place Bellecour). The Saone is represented as a woman resting on a sedate lion and the Rhone is represented by a warrior leaning against a roaring lion (by Nicolas and Guilaume Coustou).  The ornate exterior arches are decorated with fluted columns adding to the bridge's neo-classical appearance. The mauve and aquamarine colors seem very French.
The bottom flange is attached to the arch (and attached to the cross-bracing) with rivets. Similar to the Vasabron Bridge, which was discussed in a recent Happy Pontist Blog, this bridge was most likely fashioned out of wrought iron. The first steel bridge was the Eads Bridge in Saint Louis, Missouri that was built in 1874, 14 years before this bridge was constructed. However, it's possible that the middle span was rebuilt after the war using steel.
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Sunday, October 30, 2016

Bridges of Lyon, France: Passerelle du College across the Rhone River

September 2016 (45.7643, 4.8397) Passerelle du College
The Passerelle du College is a pedestrian bridge that was built to carry children to school. It was almost completed when a cable swage broke, sending workers into the Rhone where 8 people drowned. After the accident, the bridge was quickly completed (in 1845). During WWII, the bridge was determined to be a danger to the retreating German Army and one of the piers was destroyed. The bridge was carefully rebuilt after the war (in 1945).
The Passerelle du College is a three span bridge with suspension cables and stays supporting the main and back spans and additional cables without stays to help support the main span (see above photo).
Looking west across the Rhone, we can see that the piers are protected by tiny islands that have trees and perhaps a garden? The closer pier has an inscription on top commemorating its reconstruction after WWII.
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Sunday, October 23, 2016

Bridges of Lyon, France: Pont Morand across the Rhone River

September 2016 (45.7686, 4.8397) Pont Morand
We continued downstream along the Rhone a few hundred yards until we arrived at Pont Morand. Because many of the bridges across the Rhone were destroyed during WWII, the river now has many modern structures. Similar to the Pont Winston Churchill, the Pont Morand (named after the architect who designed an earlier bridge) has a functional shape that matches the moment diagram of the bridge.
The Pont Morand is a three span 187m (614 ft) long bridge that was built in 1976. Like the Pont Winston Churchill it is composed of two prestressed concrete boxes with steel braces between them to support the deck during construction. The piers have a large shear key on the north side that seems to only function as a support for the tall light posts.
The Pont Morand that was built after the war was replaced to accommodate construction of the Lyon Metro (subway) that goes under the Rhone at this location. You can see the stairway to the subway stop on the bridge aprons at each end of the bridge in the photo above. It's strange that so many of these bridges carry roads that stop at the ends of the bridge. All of these obstacles make traffic pretty awful in Lyon, which is why so many people use the Metro. I took a train during rush hour and it was as crowded as a Tokyo subway.
There are tall quay walls at each end of the bridge and so the abutments have narrow seats up against the subway vents. Note that at the abutments the Pont Morand is more like two separate bridges, Also note the runner going by (just as I snapped the picture). The east bank of the Rhone has more exercise fanatics than I've seen in most U.S. cities.
In the photo above we can see the Pont Morand superstructure resting on its haunches.The Pont Morand has a very simple appearance without the parabolic curves that we typically associate with haunched girder bridges. The roof of the Lyon Opera House can be seen above a building across the river.
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