It’s been a tough year for highways and byways leading to Big Sur, including the “mother of all landslides,” a sloughing so massive that it changed the shape of the California coast.
And, before that, it showed the failure of a 50-year-old bridge spanning Pfeiffer Canyon, which is still out.
Torrential February rains and landslides buckled the old bridge. Caltrans knocked down the impaired extension in March, and the present schedule calls for it to have the replacement up and running—or rather, up and staying in place—by early October.
With that in mind, the agency released a time-lapse video last week showing the months work of work on the new. While invoking the word “lapse” in any capacity is a risky move whenever trying to reassure the public about a disabled bit of infrastructure, in this case Caltrans hopes to visually impress upon the public the degree of labor going into the roughly $24 million rebuild.
The slightly more than six-month turnaround is thanks to Caltrans’s much-touted accelerated construction plan, explained in its Mile Marker publication earlier this year:
The new bridge will be moved across the canyon using a time-saving ‘incremental launching’ method that doesn’t require construction of multiple temporary towers in the unstable canyon.
The entire steel girder portion of the bridge superstructure will be assembled on a roller bed located on the approach roadway on the north side of the canyon. Five 63-foot-long girder sections will be bolted together to create a single 315- foot girder. Three lines of girders will be set across from each other, connected by steel cross frames
Notably, the new bridge does not make use of any support columns. According to KRON4, once the new bridge in place it will take 500 cubic yards of concrete and rebar to finally secure it.