Vance Wiley (Structural)1 Nov 19 07:24
Some points from NTSB Meeting Miami and further down, comments about loads and capacities at failure.
Very informative post.
But, do not forget that the equations have some limits:
Vu =K2*Acv
In this case (assuming slab)
Vu = 1.8x21x40 = 1512 kips...
jrs_87 (Mechanical)1 Nov 19 13:42
"Feds figured out why FIU bridge fell. Now prosecutors must decide if deaths were a crime"
https://www.miamiherald.com/news/local/crime/artic...
This is where money comes into place to avoid justice. With South Florida politics, with "some people" that are...
Vance Wiley (Structural)30 Oct 19 05:43
What is Pcr in concrete column buckling?
Thanks for the post.
Now we know of another place where we have a number for the #11 strut force in FIGG calcs. It can be used as areference despite the fact that may contain a large live load instead of the...
Note to all
I believe I have said this before. The truss can be made safe with just a little bit more of concrete and rebar in the right locations (connections) and supports under member #12. I have no problem with this type of structure. It is ok.
However, this case will scare the hell of...
One more comment.
To anybody that is not an structural engineer and it is only an inspector or contractor, the structure looks may fool them to believe that the deck act as a beam with a lot of capacity like your tipical bridge. Specially if they already know that the "stays" are fake. So...
Greetings to all
Regarding the shims under the deck, in the RFP plans it only says " place plate shim" It appears to meaan only one. But they installed 4. This is an big error because this structure was analyzed as a continuous support under the deck. Is the shims are discontinous and they...
Kestrel42 (Bioengineer)26 Oct 19 20:16
Reading through FIGGs analysis as well, Vance. I find it supremely unconvincing.
Allow me all of you to provide you a piece of information for you to decide if it is relevant or could provide an explanation for the events of the week of march 10, 2018...
mdepablo (Structural)
Take a look at the NTSB docket where all the info (more than 6000 pages) is located:
https://dms.ntsb.gov/pubdms/search/hitlist.cfm?docketID=62821&CurrentPage=1&EndRow=15&StartRow=1&order=1&sort=0&TXTSEARCHT=
The plans for construction are in documents #62 , #63 and...
I have to say that the conclusions of the NTSB (Figg used in the design lower demand and did not request in the plans the roughening note) were obvious many months ago when the plans and calculations were available to the public from FDOT (free) and FIU (for $35.00), respectively.
Oh, well...
Ingenuity (Structural)24 Oct 19 20:48
Quote (Vance Wiley)
Where did the 571 come from?
In page 1387 (Section 10) of FIGG's calcs (LUSAS results) and from simple span analysis of (DL+ PT) the number 570.6 kips appears in the Fy resultant. However, in page 1283 (Secion VII) the rebar in the...
I wish I had access to the output of all the analyses performed to look at the forces in the elements for all the relevant loads (DL, PT, and Construction LL) independently. This is because in the reports It is not clear to me if they are refering to Service loads or factored load combinations...
5Hiway.1 (Civil/Environmental)23 Oct 19 02:40
samwise753 (Structural
Last week I called the Florida Board of Professional Engineers to find out if there has been any COMPLAINTS against the EOR that signed and sealed the plans. I was told that officially there is none but that they can not say...
Vance Wiley (Structural)16 Oct 19 00:46
To answer your questions:
1 If the connection is designed assuming that with "No intentional roughening" based on AASHTO LRFD (no 1/4" roughening) is enough to transfer the shear friction, then the FDOT spec based cleaning is good enough. If you...
Note to all:
The pics show cracks in vertical column 12 which means that there is bending there. Also the #11 must have benting moment on top of comprssion forces.
The reports do not incorporate these elements into their review (not FIGG, MCM, or NTSB). These secondary or "terciary" forces...
The green Lama
Zeroing in on this: "Re-Stressing of Member 11 (Section 8). Contrary to FIGG’s instructions, no one closely monitored cracks in the north-end diaphragm during re-stressing of Member 11, even though both MCM and Structural/VSL were aware of the instruction."
This is such an...
Mr. Vance Wyley:
In conclusion, most significant finding from WJE’s research and analysis is that full-scale tests show that if the construction joint below Members 11 and 12 were roughened as required by the FDOT Standard Specifications,
Sorry, but you have been "fooled" by the WJE report...
Quote (The Mad Spaniard)
If the fillet (wedge) is compressed from #11 and from #12, and the PT bar is stressed, isn't it possible that it would "pop-up" vertically? Leaving #11 free to press more to #12. Also, given the sudden failure, don't we have additional forces due to dynamic effects (even...
Earth314159 (Structural)15 Aug 19 18:28
I should also mention that the rotation of the base of #12 increases the compression stress of the bit of concrete between #11 and #12. The compression causes a slight rotation at the base of #12 that causes the vertical crack on the south side of #12...
hokie66 (Structural)12 Aug 19 00:55
The Mad Spaniard,
So by your comments, I take it that you believe the rest of the bridge was just fine, and that the only problem was at the joint which failed first. That is a big assumption, but one which seems to be common in the recent discussions here...
hokie66 (Structural)11 Aug 19 22:30
If Berger accepted a commission like that, they neglected their primary duty to the public.
This is a wonderful comment and shows a philosophical item in our bussiness. Because it is a bussiness. My guess it that nobody at the time couuld believed that once...
