Bridges of Mexico: Bike Path on Periférico Ecológico in Puebla City

September 2017 (18.9791, -98.2206) Ciclovía del Periférico Ecológico de Puebla Ciudad

Driving south on Calle Periférico Ecológico in Puebla City I noticed a bright blue bike path in the median. Instead of an elevated bikeway like the one in the median of Hermanosa Serdán Blvd. the Ciclovía del Periférico Ecológico is 'at grade' but with elevated structures about every half mile to get on and off of this limited access expressway (see photo below).

These elevated structures include a narrow 'T' shaped superstructure on single column bents (the overcrossing), a 'C' shaped superstructure on squat four-legged trusses (the main ramp), and on/off ramps that zig-zag along the sides of the expressway.

The median has to be wide enough to accommodate bicyclists continuing their ride on each side of these elevated structures (see above). Since the resulting median could have been used to provide two extra lanes of traffic one might wonder if it's really worthwhile. Perhaps it's because I'm an avid bicyclist that I think the answer is yes!

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Bridges of Lyon, France: Passerelle de la Paix across the Rhone River

September 2016 (45.7868 degrees, 4.8545 degrees) Passerelle de la Paix

A few hundred yards downstream from the Viaduc SNCF is the Passerelle de la Paix (Footbridge of Peace). The bridge connects Cite Internationale (east of the Rhone) to Saint-Clair (west of the Rhone). The idea of a peace bridge was to bring intercultural harmony between the two communities since Cite Internationale is French and Saint Clair has a large immigrant population.

The bridge project was first proposed by the Metropolis of Lyon (Grand Lyon) in 1994. A design competition was held and eventually won in 2009 by Dietmar Feichtinger (Architects) and Schlaich, Bergermann, and Partner (Engineers). Construction began in 2012 and the bridge opened in 2014.

The 220 m (710 ft) long bridge is composed of two cantilever space truss sections. The bridge supports a timber deck on the top and another timber deck to the side with an asymmetric tubular steel structure. The two decks meet in the middle to form an 8 meter (26 ft) wide public space.

The foundations were constructed at each riverbank while the bridge was being assembled offsite. Then it was brought onsite by two barges and set in place (see photo below). Note the suspension structure that was used to support the bridge before it was placed on the foundations (photo below by Michael Zimmerman).

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Sacramento County, California Bridges: Bicycle and Railroad Bridges across Willow Creek

September 2013 (38.6681 Degrees, -121.1421 Degrees) Willow Creek Bridges

Continuing on the Jebediah Smith Auxiliary Bike Trail I came upon many Glulam bike bridges and timber railroad bridges side by side as Willow Creek jogged back and forth over what used to be the railroad right of way. The Glulam beam easily spanned the creek (for pedestrian loads) but the timber railroad beam needed support at mid-span (to carry railway live loads).

Sacramento County, California Bridges: Bicycle and Railroad Bridges across Willow Creek by Mark Yashinsky is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 3.0 United States License.