🚀 go-pugleaf

In article <3B72B2AA.CA9FBCA1@thegrid.net>, Paul S. Highland says...
(snip)
>
>The freeway that collapsed in the Loma Prieta quake in 1989 was a section of I-880 in Oakland.  It
>has since been rebuilt on a slightly different alignment as a single-level structure.  (Took 'em
>long enough to do it, too.)
>
>Two other double-deck freeways in San Francisco were damaged.  The Embarcadero Freeway was torn down
>completely, and a section of US-101 was single-decked, if I recall correctly.

That section of US-101, the Central Freeway, will be shortened and rebuilt.  It
will be a single deck, as you mentioned, and will come to grade at Market Street
instead of continuing to Fell/Oak.  Past Market St., the roadway will become
Octavia Bl.  This will just make traffic problems in San Francisco worse but the
anti-freeway people there had the last word.

>
>I believe all those structures were built in the 1950s with inadequate bracing.  While construction
>standards have improved vastly since then, many people might still have fears about double-deck
>structures being unsafe.

The problem was poor engineering.  The supports were placed on the outside and
when the earthquake hit, they all just collapsed like pancakes.

Caltrans has learned.  Newer double-deck structures (like many of the HOV to HOV
connectors on LA freeways as well as the I-110 Transitway have thick "T" shaped
center posts running below the viaduct.  This is much safer and will better
support the roadway in an earthquake.

Don

>
>=== Paul S. Highland

http://www.fixtraffic.org  Fighting for the Rebuilding and Expansion of Southern
California's Freeway and Highway System
Discussion at http://groups.yahoo.com/group/sc_hwys
Discuss the 710 Fwy Gap Closure--Pro or Con--at
http://groups.yahoo.com/group/Go_710