WEST SEATTLE BRIDGE: You asked, so we asked – weight restriction?

(WSB photo, West Seattle Bridge work platform, late July)

When SDOT announced last week that the West Seattle Bridge is expected to reopen Sunday, September 18th, WSB commenters had some follow-up questions. Among them: Will there be a weight restriction on the bridge? We asked, and today we got the answer: No. SDOT spokesperson Ethan Bergerson says, “We are not planning any weight restrictions for vehicles on the bridge. Vehicles would still need to follow the statewide laws governing maximum weight limits to drive on public roads.” (Find those here.) There are weight-limit signs on the bridge now, as we noticed when visiting last Tuesday, but Bergerson explains that they “were placed for construction crews before the post-tensioning work was completed. Now that that work is done, the bridge is much stronger and those signs will be removed by the time the bridge opens.” He also reiterated the plan – noted again in our report last week – for load testing before the bridge reopens, “in which we will drive heavy equipment over the bridge to simulate traffic and let engineers monitor the structure’s response in real-time and confirm that the repairs are working as expected.” If the closure ends on September 18th as currently planned, that’ll be just five days short of 2 1/2 years since its sudden closure on March 23, 2020.

Pat August 15, 2022 (9:31 pm)

Already ?

Watertowerjim August 16, 2022 (5:37 am)

Common sense makes one think idling buses and Nucor rebar trucks can’t be “good” for the bridge. I’d love to see an answer to those specific examples. I am not an engineer so save your snarky remarks for the engineers who let this happen in the first place. Unquestioned faith in “experts” has landed us in all kinds of trouble throughout history – including two and a half years without this bridge.

Jethro Marx August 16, 2022 (11:23 am)

The same sense would tell you that your refrigerator is damaging your kitchen floor, right? Building public infrastructure using “common” sense is a recipe for far worse than a bridge in need of repairs.
Neighbor August 16, 2022 (11:51 am)

This question comes up a lot and has been answered many times. The weight of traffic is minor compared to the weight of the bridge itself. Even hundreds of cars doesn’t add significant weight to a structure like a concrete bridge. A bus, concrete, or rebar truck doesn’t matter. The problem with “common sense” is that the world isn’t simple and initial reactions are rarely correct. It’s more like common ignorance.
J August 16, 2022 (12:54 pm)

Engineers don’t typically have any say. In a contracted project like this one, the project owner usually defines budget constraints which engineers are required to design within, and that design is then handed off to crews who go out and build it exactly as designed. A cheap bridge design (concrete and rebar that is brittle with weak tensile capacity to span long distances like we have in the WS bridge) can be recommended against by engineers, but ultimately, it is the owner who is funding the project that makes the final call on if they want a cheap bridge built, or one of higher quality that would last much longer – one with structural steel and post-tensioned concrete for example. I agree with you that engineers should be in the driver seat of design, and they are when it comes to creating one, but they can only design to what funding is available. There are other project delivery methods out there where engineers work with owners on best-value and not cheapest end product, but typically government/municipal projects like this one, I assume, are done as cheap as possible. I agree with you we need to do better, just my observations in construction – coming from an engineer.
Eamon August 16, 2022 (3:07 pm)

Busses, oh come on….as if those same people who ride busses were all driving cars would be much better. Like…what??

Hammer in Hand August 16, 2022 (6:26 am)

So Metro who’s busses are over weigh per axel gets a free pass because of a Fed exemption 🤷‍♂️🤦‍♂️Build the roads and Break them just look at all the replace work around Westwood and Barton those road panels are the result of busses

Neighbor August 16, 2022 (11:56 am)

Yes that makes sense to me? The buses are more efficient so we make an exception. If more vehicles weighed as much as a bus the roads would just break down faster. One bus is dozens of cars that aren’t on the road causing wear. Yeah the roads around bus stops break down so we repair them. It’s a jobs program. Everyone wins.
Davey August 16, 2022 (2:31 pm)

Hammer,Thank you for acknowledging this. This is literally what broke the dumb bridge in the first place. Maybe they should use the low bridge from now on………
Kevin on Delridge August 16, 2022 (5:31 pm)

You’re putting The Onion out of business, kudos.

Yup August 16, 2022 (7:29 am)

Can’t weight…

Dee Swindon August 16, 2022 (8:05 am)

It would be nice to have a raffle or something per who is the first person to drive over the bridge. We use to talk about that at Shakey’s pizza on 35th Ave. in the early 80s after Soccer games.

Joe August 16, 2022 (8:59 am)

So is there still going to be a bridge reopening celebration where people will be able to walk/ride over the bridge before it opens to traffic?

WSB August 16, 2022 (9:06 am)

No.
Neighbor August 16, 2022 (11:57 am)

There was never a plan for walking or biking on the bridge. They want to open it ASAP so people can actually use it.
- WSB August 16, 2022 (12:36 pm)
  
  Yes, there were tentative plans, as we have reported, led by community groups. SDOT finally said “no events on the bridge.”

Marty2 August 16, 2022 (10:39 am)

I hope they use a fully loaded Rapid Ride Bus as one of the test vehicles.

Neighbor August 16, 2022 (11:59 am)

Sounds like they are going to use something much heavier than that. They mention “heavy equipment”. They need to simulate the load of traffic, not just a single vehicle.

west sea neighbor August 16, 2022 (10:55 am)

Well this is a weighty consideration…

Peter August 16, 2022 (12:23 pm)

There’s clearly a coordinated effort to use the bridge repairs as an excuse to attack critically needed bus service. So if you have any actual proof that buses caused the damage or will cause further damage, please present it.

reed August 16, 2022 (1:24 pm)

They don’t. This is just preemptive chest thumping about buses getting priority access to the 99 off ramp. I give it one week after the bridge opening for this comment section to settle back into the daily gripes we had before the bridge closure.
Charles August 16, 2022 (3:14 pm)

Could I borrow your copy of the original design calculations so I can check the dead and live loads designed for, please?
Hammer in Hand August 16, 2022 (3:57 pm)

For damage cause by Busses look no further than any bus route. Specifically Westwood village. 26th and Barton. Those concert panel damage was not cause by car. That was done by all the busses whe. They put in the Transit Station
Jethro Marx August 16, 2022 (4:02 pm)

I think you will have to expand a bit on what you mean by ‘coordinated.’ Couldn’t it just be few random semi-anonymous internet commenters? Also, is complaining about an exemption for overweight axles the same as attacking bus service, as a concept? Really?

nothend August 16, 2022 (2:31 pm)

Original design seems to assume 5 lanes of traffic (not the current 7) with only two trucks on the bridge at the same time. ” 2.5 Live Load
Live load in the main span produces positive moment (tension in the bottom slab) at this
location. The design live load was based on 5 lanes of HS20 loading reduced for the
improbability of multiple lane loading. It is conceivable that two fully loaded trucks (36 tons
each) could be on the bridge simultaneously.” https://www.seattle.gov/documents/Departments/SDOT/BridgeStairsProgram/West%20Seattle%20Bridge/HDR%20SDOT%20-%20WSB%20Report_Final_3-17-2014.pdf  I’m thinking it was quite common to see all 7 lanes full of traffic,,, and for sure the eastbound 4 lanes packed to gridlock with four or five 60,000 lb busses and three or four 100,000 pound rebar trucks from the old Youngstown mill. Ban the buses and trucks

Neighbor August 17, 2022 (10:54 am)

Talk about finding what you are looking for. The conclusion only mentions the Nisqually quake as a possible cause. It also clearly says the cracking doesn’t reduce the capacity of the bridge.

WS Resident August 16, 2022 (4:29 pm)

Was keeping the restrictions on the lower bridge considered with routing bus and freight traffic on it? The load analysis are most likely correct but may error on missing factors. This is how we are repairing a bridge that should be lasting many decades more based on the engineering calculations.

WSB August 16, 2022 (5:37 pm)

I don’t know whether they were considered, but SDOT has repeatedly reiterated that everything will be going back to the way it was, including trucks and buses on the high bridge.

WSRob August 17, 2022 (9:23 am)

I’m more interested in SDOTs plan for maintaining the bearings that allow the bridge to float a bit when the two anchor points on either side of the bridge move in opposite directions. Wasn’t a ‘locked’ bearing part of the overall root cause that exacerbated the cracking (in addition to the other failures)?

Eddie August 17, 2022 (4:55 pm)

Any idea when the new bus routes will be posted?

Debora August 17, 2022 (8:04 pm)

What about the increased weight of EVs? Has that been considered in the bridge weight capacity ?Aren’t EVs up to 1000 lbs heavier than gas powered vehicles and harder on roads?

Sorry, comment time is over.