A better way to build a freeway
Mexico City is enormous–25 million people and growing. The city isn’t growing upward, like Hong Kong, but outward, constantly engulfing the outlying villages. Moving all these people around every day is a logistical nightmare as the traffic gets ever thicker and the “rush hour” expands to all day and half the night.
One of the things that helps is the periferico, the elevated peripheral freeway that encircles the city, just like the beltway in Washington D.C., or the peripherique in Paris. The problem is how to keep building more of it without bring the city to a standstill.
The construction technique they are using is brilliant. They build the road in a factory, and just truck it in.
Once the towers are in place, the freeway is factory built and trucked into place. This happens at night so disruption is held to a minimum. Then huge movable cranes lift the blocks of freeway into place:
The blocks you see below are just the base, tying the towers together–there will be 3 or 4 lanes of freeway placed on top.
This method gets the freeway build very quickly, with the a very low amount of disruption to the already clogged surface roads. I expect it’s cheaper, too, building the huge pieces in factories where everything can be planned and repeated and there are efficiencies of scale.
People often look down on Mexico as a third world country, but their building process for this freeway is something I wish I saw happening around here. I cant forget that the Loma Prieta earthquake was in 1989 and the Bay Bridge still isn’t finished. (Remembering that the bridge only took 3 years to build in the first place in 1939, before computers)