WEST SEATTLE BRIDGE CLOSURE: Wondering ‘what ARE they doing up there?’ Here’s the answer

(SDOT photo: Small “syringes” placed into affected areas, used to channel epoxy into cracks)

You’ve heard that stabilization work is under way on the five-months-closed West Seattle Bridge. So what EXACTLY is being done? SDOT just launched a new weekly email update. From the first one:

Kraemer North America, our contractor for the stabilization work, is on the bridge every Monday through Saturday from 6 AM to 4:30 PM to stabilize the West Seattle High-Rise Bridge. The stabilization work, which includes wrapping weakened areas of the bridge in carbon fiber, adding post-tensioning inside the girders, and epoxy-injecting cracks wider than 0.3mm, is expected to continue at a safe but expedited pace over the course of the next several months.

Next week, the contractor is planning to:

Continue to inspect cracks
Fill cracks with epoxy
Place carbon fiber wrap around recently filled cracks
Begin to install the post tensioning system

During this work, you will see some crews working on top and underneath the bridge. You will also see scaffolding and crews working on platforms suspended under the bridge. There is additional work taking place inside the bridge – including monitoring cracks and preparing for the installation of the additional post-tensioning strands – that you will not be able to see. We do not anticipate any additional traffic impacts from the West Seattle High-Rise Bridge construction work over the next couple weeks.

More bridge-related info is coming up this evening in our report on last night’s West Seattle Transportation Coalition meeting. Meantime, if you want to be on SDOT’s bridge-related mailing list, the subscription link is on this page.

Findlay August 28, 2020 (8:03 pm)

This standalone syringe photo really doesn’t give me much confidence of the professionalism of these repairs.

Kravitz August 28, 2020 (8:43 pm)

Is Phil Swift of Flex Seal infomercial fame on this job?

Alice August 28, 2020 (9:05 pm)

I was not aware that there was epoxy that worked on concrete! I guess I’m not a materials scientist!

Gerald August 29, 2020 (6:34 am)

And after many months of repairs, we will still end up having to replace the bridge.

What a waste of time and resources.

Stevie J August 29, 2020 (10:08 am)

As has been mentioned on this blog 100 times, the bridge needs to be stabilized even if they end up replacing it. We can’t risk the safety of the workers who would deconstruct the bridge and damage to the waterway just because you want to drive to Costco faster.
- Costco Faster August 30, 2020 (4:35 am)
  
  Yes. Those of us with families and lives who trusted that Seattle gov and voters would be competent enough to keep a bridge open when we moved from CA to Seattle a few years…yes, we want to drive to Costco faster. It’s what normal humans want to do. It’s why we chose to live in the dark and rain…to drive to Costco faster. Yes.
  - Joseph P Egan September 4, 2020 (1:18 pm)
    
    I would drive past the First Ave S bridge on into Tukwila and the Costco store there. Avoid the Seattle FAT tax on Soda and other Seattle levied taxes. The traffic is less congested than 4th Ave S and the service station larger.

JayDee August 29, 2020 (8:54 am)

I’ve wondered about the carbon fiber. Is it really to strengthen the bridge, or to keep chunks of the bridge from falling randomly? Both would be great, but I’d be surprised if the carbon fiber+adhesive is strong enough to resist the shear of a large hunk of concrete from dropping. If anyone with knowledge can chime in that would be great.

Tsurly August 29, 2020 (9:57 am)

Strengthen. It creates a new stress complex that works with the existing components. Pretty slick stuff actually. It’s light weight, easy to install, durable, and highly resistant to corrosion/weathering. Generally speaking, and for comparison, carbon fiber/resin wraps have a tensile strength around 10X that of steel.

jissy August 29, 2020 (9:15 am)

Wow, thought at first that was duct tape holding those in and thought, Hmmmmm, yep, that’s SDOT-like.

Jim August 29, 2020 (9:22 am)

Next time maybe they will try duct tape.I would like to know when people can drive on the bridge, seems like many places you drive in West Seattle they are tearing up the street.When are they going to fix the messed up street by Target 🎯?

OldLady August 29, 2020 (4:42 pm)

@Jim you mean where it feels like you’re on a POGO Stick! :>)

wetone August 29, 2020 (10:21 am)

Description of photo “syringes” should say “ports” Ports are where the epoxy injection pump is hooked up for injecting epoxy, then cap (red piece) installed. Gray stuff is epoxy paste which seals outside of crack so epoxy is directed through out cracked area. The paste is also used to seal ports to areas to be injected. Epoxy if applied correctly has more strength than concrete.

WSB August 29, 2020 (10:32 am)

That was SDOT’s term, not mine – they later published the “email update” here, and it’s there too – fwiw.
https://sdotblog.seattle.gov/2020/08/28/weekly-update-west-seattle-high-rise-bridge-stabilization/

DeadEndMarc August 29, 2020 (2:16 pm)

I like that the Carbon Fiber is ten times stronger than steel.What adhesive is up to that task?Wood-glue works because it is stronger than the ‘wood’.Will this adhesive allow stressed concrete can break off elsewhere?IF it is a full carbon fiber wrap/covering, HOW will new cracks be visible?Engineering is outside of my area of expertise. I’d think these questionswere fairly basic to the experts. Can anyone with knowledge elaborate?Thanks.

wetone August 29, 2020 (2:38 pm)

Might be what SDOT’s term is, but it is not what the parts are called. Simple as that. Who ever wrote story was not familiar with process evidently……

Mj August 29, 2020 (3:24 pm)

There are way more hours each week they could be working. It’s time for the hours to be cranked up and get the work done post haste.

Tsurly August 29, 2020 (4:52 pm)

Pushing 12 hours a day six days a week is cranking it MJ. You know what happens when people work that long each day without a day off? Fatigue sets in and injuries or mistakes happen. Additionally, the resins used with the wrap do have curing times, so there are limitations as to what can be done in a work shift.

Mj August 29, 2020 (7:37 pm)

Tsurly check your math, I see 10 hour days. Adding a second shift crew is what believe needs to happen.

Tsurly August 29, 2020 (9:09 pm)

My math is fine, and accounts for the reality that is 10 hours onsite plus commute time to and from the site. I’ve done my fair share of dam inspections, and working at heights, with heavy tools, in the elements all day, similar to what these crews are doing, wears on you. Regarding more shifts, it seems you ignored the fact the the materials they are using having curing times, generally exceeding 24 hours.

Mj August 30, 2020 (3:55 pm)

Tsurly it’s a big structure that from all accounts is fixable, expediting the repair is imperative. The T5 project is scheduled to be on line next year presuming the project, and good paying union job, does not become a casualty of the bridge.

Joseph P Egan September 4, 2020 (3:17 pm)

Since West Marginal is now carrying the majority of WS traffic, why is W Marginal not receiving any maintenance? Either the city should force the rail road owners of the unused, unmaintained, rail crossing about 6 blocks S of THE BRIDGE, to repair or remove said crossing or the city remove the crossing .

A little traffic enforcement in the West bound lanes of W Marginal leading up to Chelan Ave SW intersection with Delridge Way SW to stop lane jumping over into west bound Spokane SW traffic from Chelan Ave SW would improve safety for the right hand lane..

Sorry, comment time is over.