More CRC Happenings



18 responses to “More CRC Happenings”

  1. So we’re paying $4 billion for something that looks ugly? Wonderful.

    (As an aside, my mother mentioned a while ago that she actually prefers a bridge with no superstructure, since that obstructs the view from the bridge of Mt. Hood. So I guess your mileage may vary on this one.)

  2. Doesn’t the good ped/bike aspect trump the “ugly” design? I’d rather cross the river under the cover of the upper deck (less noisy and hectic than up top between east-west lanes) and stay dry/shaded. The least expensive bridge option seems the best for ped/bike use. Cheaper too. Could all the savings be better applied to artwork, other infrastructure, etc.?

  3. If the bike/ped facility is enclosed the concern of advocates is that it be well-lit, regularly cleaned and have security features like call boxes within reasonable distances.

    Nobody wants to bike across the river in a dark cave. The devil is in the details to make it a comfortable and appealing experience.

  4. “The bridge panel chair has stressed that much of the aesthetic and design discussion can occur after the
    bridge type has been decided. His presentations included an example of how a relatively standard
    bridge type can result in an award winning architectural design.
    The Departments agree that aesthetics should be recognized as an important element and evaluated in
    the context of all of the competing needs. We also agree that a comprehensive public conversation
    about aesthetics should occur after the bridge type is selected.”

    I’ve personally seen really beautiful new trusswork in Europe. I’ve also seen really ugly arch and cable-stayed work in America. My personal opinion (objection) is more geared toward the other improvements in the project that are not being discussed: the 5 miles of highway widening and on/ off ramp lengthening. That crap is going to be UGLY.

  5. An important point to keep in mind: The truss design of the bridge can curve, giving engineers a lot more flexibility in routing. Both arch and cable-stayed designs must be straight.

    In short, there is a very good functional reason, besides cost, to prefer the “ugly” design.

    (Besides. It seems like it should be perfectly possible to add faux, non-structural arches or “suspension” cables to the bridge–ones that if not being forced to bear the bridge’s weight, can be made to curve as well. I don’t consider such ornamentation to be important, especially if it costs seven or eight figures, but some folks think this sort of thing is important…)

  6. I do prefer the attractive designs, but since I’m against the project in its current form anyway, the actual design is irrelevant to me. As Chris points out, we still don’t have any way to pay for this monstrosity. As mentioned over on Blue Oregon, ODOT and WSDOT are approaching this like a couple of homeless guys trying to figure out whether they’d prefer a Ferrari or the Lamborghini.

  7. Oh yeah, I should have been clearer, if there is a significant cost saving, we should definitely go with the simpler structure. It’s just frustrating.

    I’m definitely down with non-functional ornaments.

  8. I would question the seismic safety of the flat design. Perfectly fine for the normal max. 6.8 earthquakes we have experienced here. But I’m not so sure it would be if we are trying to plan for a Richter 9. In the 6.9 Loma Prieta earthquake of 1989 the two level concrete Cypress Viaduct crumbled big-time. I believe 1.2 miles of it fell down. True, the reinforcing of that era was not up to today’s standards; but the steel, Oakland-Bay Bridge had only two 5 lane wide x 40 ft. sections come down, and one person was killed when they drove into the fallen section.

    “CYPRESS VIADUCT
    The earthquake caused the Cypress Viaduct to collapse, resulting in 42 deaths. The Viaduct was a raised freeway which was part of the Nimitz freeway in Oakland, which is Interstate 880. The Viaduct had two traffic decks.

    Resonant vibration caused 50 of the 124 spans of the Viaduct to collapse. The reinforced concrete frames of those spans were mounted on weak soil. As a result, the natural frequency of those spans coincided with the forcing frequency of the earthquake ground motion. The Viaduct structure thus amplified the ground motion. The spans suffered increasing vertical motion. Cracks formed in the support frames. Finally, the upper roadway collapsed, slamming down on the lower road.
    The remaining spans which were mounted on firm soil withstood the earthquake.”
    http://www.vibrationdata.com/earthquakes/lomaprieta.htm

    photo “wreckage of Cypress Viaduct:
    http://www.corbisimages.com/Enlargement/UG001977.html

    photo of the damaged section(s) of the Bay Bridge
    http://www.flickr.com/photos/sanbeiji/220645446/

    I also wonder how stable the relatively long sections of the cable-stayed design would be. The arch designs divides the roadway into smaller sections, but would need modern bearings to give it some flexibility.

  9. I’m not a civil engineer, and I suspect that neither is anyone else here–but the Cypress Viaduct had its foundation on top of soils which liquified due to the earthquake vibrations. I would expect that part of a modern seismic-safe bridge would be a foundation which extends to bedrock, no matter what the design of the bridge is.

  10. ODOT’s ugly bridge/freeway across the Willamette has compromised Portland’s riverfront and the potential for eastside development for almost 50 years. Even Glenn Jackson, then the head of the OHC (Highway), said the Marquam Bridge/Eastbank Freeway was a mistake. Now ODOT wants to do the same across the Columbia. The project should be taken out of the DOTs’ hands before its too late.

  11. Nobody wants to bike across the river in a dark cave.

    I kinda do! But I also wish I lived in an old city with all sorts of nooks and crannies and alleyways.

  12. I’m not sure if even going to bedrock establishes that much protection during more severe events. However, I think the likelihood of a subduction quake tends to be exaggerated here in the Portland area; much more likely out on the coast. But if much of the reason for replacing the existing I-5 bridges is that they won’t withstand the higher level events, then we need to ask those more probing questions. We’ve been through a small number of 6.5 to 6.8 events in our recorded history and as far as I know there is no observed bridge damage.

    In the 1964 Valdez quake there were a lot of permanent elevation changes. I can see how going to bedrock would prevent liquefaction damage; but what if the bedrock moves? So is it worth it to make the investment of preparation for a higher level events if you can’t really predict how deep the ground changes could be? I’d rather look into modern bearing systems and see what the latest developments for those are, esp. as applied to retrofitting. I’m not an engineer either, but I know a good portion of the seismic upgrading I have worked on has been very questionable if not patently useless; it was just theories.

    In the 2009 ODOT report about vulnerability of Oregon structures it clearly shows the higher risk zone that Seattle is in as being located much further west at Portland’s latitude.

  13. Lenny,

    The problem with the Marquam Bridge isn’t the bridge itself, but what it does when it lands on the eastern shore. Were I-5 to disappear into a tunnel several blocks east of the river, and not emerge until Sullivan’s Gulch, many of the objections to the bridge would go away.

    Likewise, were the Marquam to be retrofitted with a faux arch, the primary objection to it would not go away.

    The CRC, for all its warts, isn’t going to run along the Columbia River and separate the river from the community. SR14 and the BSNF tracks do that just fine today. :)

  14. Yes and no. The Marquam’s problems are many but the bridge itself is one of the problems, not even mentioning it cutting of the east side from the river. Not unexpectedly, people expect something built with gov’t money to be well built and aesthetically pleasing. Compare the Marquam to the decade younger Fremont Bridge, which the casual observer would wish had better approaches leading to it, but is at the same time a beloved bridge while being a highway bridge.

    Not sure how an ugly bridge is going to help in the cause of getting the Or. legislature to appropriate the necessary funds.

Leave a Reply to Jim Lee Cancel reply

Your email address will not be published. Required fields are marked *