Under the deck of a reinforced concrete single span overcrossing (a bridge over the highway) is what I would call a structural steel space truss. It's made up of eight-legged elements connecting the concrete slab to longitudinal and transverse steel elements. Apparently, these thin elements are strong enough to increase the bending resistance of this structure.
This type of structure is apparently very popular in Colima. There is a water main supported by a similar structure 140 ft away, and single span and two span bridge undercrossings (a bridge carrying the highway) a few miles to the north.
Mexico's Bridges: Overcrossing near Tonila by Mark Yashinsky is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 3.0 United States License.
Unfortunately, this bridge has been built several times based on the same design. At least one has failed already catastrophically, the others suffer from severe fatigue and corrosion damages. Maintenance of this structures is fiddly and basically a nightmare. All of the bridges of this kind have already experienced extensive repairs and reinforcements, and several are being replaced right now.
ReplyDeleteThis is a wonderful example of a badly designed structure and in most cases also poor workmanship.
Thanks for your collection of Mexican bridges and your impressions.
NORRIN : MORE THAN ONE CONCRETE BRIDGE HAS FAILED AND YOU DONT SAY THAT THEY ARE "BADLY DESIGNED STRUCTURES", PRECAST BEAMS THE SAME.
ReplyDeleteI HAVE SEEN AT MEXICO PRE STRESS BEAM BRIDGES THAT THEY COLLAPSE BEFORE OPENED TO TRAFFIC.
I HAVE SEEN BRIDGES WITH MORE THAN 25 YEARS, AND THEY HAVENT RECEIVE MAINTENANCE (NOT RE-PAINT, NOT SUPPORT CLEANING, NOT NOTHING) AND THEY ARE OK.
AT MEXICO THE PROBLEM ARENT THE BRIDGES. THE PROBLEM IS THAT WE THINK THAT THE BRIDGES DONT NEED MAINTENANCE AND WE NEVER GIVE MAINTENANCE TO THE BRIDGES. "POLITICAL MEXICAN THINGS"
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