Ferry Dock Collapse 13

[dik]

"At least seven people were killed and several others injured Saturday after part of a ferry dock collapsed on Georgia’s Sapelo Island, according to the Georgia Department of Natural Resources.

It happened as crowds gathered on the island for a celebration of its tiny Gullah-Geechee community of Black slave descendants.

At least 20 people were plunged into the water when a gangway collapsed on the visitor ferry dock shortly before 4 p.m., Georgia DNR Capt. Chris Hodge said at a Saturday night news conference. A McIntosh County commissioner previously said a boat hit the dock but a DNR spokesperson later told The Associated Press there was no collision and it is unclear why the dock collapsed."

https://www.cnn.com/2024/10/19/us/sapelo-island-georgia-boat-dock-collapse/index.html

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

 

[LittleInch]

Crescents Insurance Co must be very worried, hence compete lack of statements from them.

As will the PE who stamped the drawings and design calculations.

It does call out a Heavy Duty HD gangway. The top rail is shown in their typical drg as 3 x3 square. As built uses a round tube. Plus it's wider than the max width shown.

 

[human909]

As will the PE who stamped the drawings and design calculations.

I still wonder if there are design calculations. From my rudimentary inspection I'd be surprised if it would pass 50psf let alone 100psf. The loading on the gangway still sounds well under 50psf that is 32,000lbs! Which means little to me 14,500kg or 150people. There are plenty of incompetent engineers out there but to be this far off one questions if an engineer did any calculations.

 

[LittleInch]

I doubt we will ever find out, or at least not until all the court cases have finished.

There is alos the issue of how exactly this was made, the section lengths used and the welding quality.

But on the face of it it does appear to be rather skinny to say the least and with the change in truss type and possibly top rail material, $3,500 for design does start to look rather low.

 

[Garbage1]

Crescent's Invoice shows an invoiced total amount of $642.11 charge for PE Stamped Drawings, for all the items on Sapelo Island Visitors Center Invoice. That amount is calculatd as .18436 of the $3500.00 Rate Amount.

How much is PE willing to do for $642.11? Doubtful PE did actual design. At best PE verified to his/her satisfaction that drawing met specifications and stamped and signed it?

 

[LittleInch]

Crescent's Invoice shows an invoiced total amount of $642.11 charge for PE Stamped Drawings, for all the items on Sapelo Island Visitors Center Invoice. That amount is calculatd as .18436 of the $3500.00 Rate Amount.

How much is PE willing to do for $642.11? Doubtful PE did actual design. At best PE verified to his/her satisfaction that drawing met specifications and stamped and signed it?

If you look closely this is clearly just an up front payment of $15,000 / deposit and they've adjusted the percentages to arrive at that exact figure. It's just the first invoice and it is clear to me that the total amount allowed for PE stamping is $3,500

 

[Garbage1]

OK, I see it is partial billing, however $3500.00 stamp is for multiple items (gangways (plural), fixed pier, floating dock, handrails).

Very confusing invoice as it states in the terms field that amounts are due in 3 increments: 35% then 65% then full balance.

35% of $75,232.80 total for rate items including 8% tax comes to $26,331.48 and NOT the $15,000.00 amount invoiced.

Also mentions Plural Gangways but only invoicing for one on this invoice.

 

[Garbage1]

SymPle could you please unload a better image for this drawing. I find it interesting top truss is shown as Howe, and lower truss is depicted at Pratt.

 

[Sym P. le]

The Crescent Invoice is interesting in that it covers two gangways and a "fixed pier system", yet there is one additional gangway in the project that is not covered. Also the 5'x30' structure looks far more robust than the 80' gangway.

 

[Sym P. le]

... could you please unload a better image for this drawing.

Dwg 2-C6.00, as it pertained to the Meridian installation, was deducted from the scope of work awarded to Centennial. Compare with Dwg 1-C7.00 which pertained to the Marsh installation that was awarded to Centennial. I've also uploaded Dwg C6.00 which was included in the Meridian package a year later. Sure this is pedantic, but it gives an idea of the morass of documents being made available for public inspection.

 

[Garbage1]

Thanks SymPle for uploading the partial "morass" of documents.........(excellent choice of wording, BTW). Note 1 says it all...... "SEE MANUFACTURE'S SPECIFICATIONS FOR EXACT SIZING OF ALL RAILING SUPPORTS, POSTS, DECKING, ETC."

So Stamped design drawing by S&W appears to rule on form/fit/functional envelop, while actual manufacture's specifications rules on sizing of members? Design layout depicts a Howe Type truss configuration, and Crescent delivered a Howe Truss configuration. However, truss member sizing appears to be sized for a Pratt configuration or an upside down Howe?

Your earlier post of Georgia DNR's loading requirements are not referenced or mentioned on design drawing, which is troubling, especially when it cites manufacture's sizing rules without providing any loading requirements?

Obviously without seeing the complete contract package and subcontractor/supplier manufacturing contracts and submissions along with their Stamped drawings, we can not compare to original Ga DNR loading requirements.

You state these documents are open to the public, yet I can not find anywhere on Ga DNR's Web site a link to the Dropbox they are uploading documents to?

Would you please provide this "Public Dropbox" link?

BTW, apparently since I am a newbie to this site, everything I have posted (4 posts only in this thread) requires Moderator Approval before showing up on this Web Site for public consumption. So far times have varied from 30 minutes to a 2 hour delay before my comments are displayed. If this continues I will just quit posting. My earlier comments (Posts 106 and 107) displayed long after SymPle's Post # 108 had displayed, yet my earlier post's showed up in the order they were received by Web Master.

 

[Sym P. le]

Garbage, thanks for your explanation on the timing of your postings. I was wondering why I missed them earlier. Hang tight with the reviews. You may have to post a few more times to clear the troll hurdle. As to the DropBox, you may have to receive an invite from the media contact found here ---> Georgia Department of National Resources - Sapelo Island Incident.

As to the gangway designs, it seems the intention was to source adequate products from the marketplace rather than redesigning them time and again. The fact that the marketplace failed is a head scratcher. How the specification requirements rattle through the bid/award/procurement process is another matter.

Thanks for weighing in.

 

[LittleInch]

I've never seen or heard of the delay you speak of.

We have a new website very recently so this might be causing some delay in posting.

Try reporting your own list and ask why as this is unusual.

 

[Garbage1]

A banner shows up after posting, that says something along the lines of 'post has been sent to moderator and will not be available for public viewing until moderator approves it.' We will see if it shows up after this post, such that I can get a screen shot of it.

Edit: Image Below of message for this post, before edit.

 

[Garbage1]

Took 35 minutes to clear moderator on message #113, but now this message #114 went right away?

Two messages between 113 and 114 got deleted by moderator, but I have no idea why?

Got this private message saying "We have removed new user posting restrictions on your account"........

 

[3DDave]

Garbage1,​

An existing problem on this site has been spammers. They make a new account and promptly flood it with, well, garbage.

It appears the new software has a way to stop the first comments by new accounts to prevent that.

"We have removed new user posting restrictions on your account" is literally the message saying you are accepted to make further posts.

The moderator isn't a hawk watching every second, so there of course is a delay for that person to get time to deal with the notification along with whatever job(s) they have.

 

[Sym P. le]

A dump of 30 documents pertaining to Crescent Equipment today. Don't hold your breath, I don't see any engineering/shop drawings for the current gangways.

Here is what I see first.



I highlight the weld on the side rail because it exhibits the same "smut" present on all of the tacks. As Crescent acknowledges, these side rail welds are more critical to the integrity of the structure. I question the quality of workmanship which allowed this contamination to persist.




Side rail extrusion profile? The decking could only be stitched topside to the extruded tab. I can't see how the bottom side of the decking is welded, if at all. It may just rest on the side rail extrusion.

 

[Sym P. le]

Another 80' install that collapsed two years ago in St. Mary's GA.


First Coast News - Details on what caused walkway on dock to collapse in St. Marys (Youtube.com)

This caused some consternation. The language is not quite as bad as the dismissive indifference that led to the billion dollar settlement at Champlain Towers.



GDNA is seen working directly with Crescent ... though Lisa Anderson is likely from Custom Marine Construction, Townsend, GA and the Sapelo Community Dock is on Post Office Creek. There is no doubt that Bellingham docks and Crescent gangways are ubiquitous in local marine installations and as such, relied upon by professional designers.

 

[Garbage1]

Another Crescent 80' Howe with small diagonals and larger vertical truss members.

The trend has emerged........... Ga DNR works sole source directly with local supplier as a vendor of a manufactured product, and not as an fabricating and installing subcontractor. Thus limiting liability claims against Crescent, since Crescent delivered product to Ga DNR who performed installation of vendor product.

Ga DNR requires round top rail, which eliminates competition in a 'heavy duty commercial' gangway.

Crescent more than willing to provide their round top rail product in accordance with their design specifications.

Thus Ga DNR claiming their original spec had far higher loading requirements, but the paper trail likely will show budget overruns forced dropping design specification and accepting manufactures lower load capacity product.

St Mary's looks like failure at hinge with only 20 human loading.

I am now sensing that dead snake smell!

This now looking like a Federal Investigation needed since Crescent sells in at least two states (Florida, Georgia), according to evidence messaged on this thread.

 

[Sym P. le]

Let's not get ahead of ourselves.

From my earlier posted image of the Meridian gangway, I think I can see a series of tacks where the deck planks are attached to the side extrusion. That doesn't give me a warm fuzzy feeling at all given the poor quality of welding on the underside. I was thinking the center rail could add some strength to the structure but if the posts are merely welded to the deck planks, I'm not so sure.

Edit: The center rail on the Marsh gangway does not include the two lower rub plates. I'm looking for a better photo.

 

[Garbage1]

St Mary's Hinge Failure

St Mary's gangway failure at gangway side of hinge. Hinge mount to dock looks ok. Hinge pin deformed equally at both ends with aluminum hinge loss of connection to gangway. Failure appears to be gangway failure rather than installation failure.

Edit: About 20 people on gangway at failure and about 3 year old gangway. We need to know manufactures design loading specification, and allowable deflection. Witnesses mention this gangway was noticeably flexable too. Fatigue failure from excessive deflection of material and welds due to not being designed for unrestricted loading control?