Thanks 3DDave, and I do mean that sincerely, I guess I was hoping after waiting so long for the NTSB findings to be made public that some of the other facets of the design and methodology would be explored. Maybe such recommendations are best left to the Code Committees and researchers.
FIGG was criticized in the course of the NTSB investigation for not applying a 1.05 factor for a non-reductant member(s)/structure. I wish I knew actual loads within 5 percent, other than fresh water, for any structure I have ever designed. In my mind increasing the load by 1.05 does very...
I just keep coming back to; Looks like a duck, quacks like a duck, walks like a duck, must be a goat, mentality that appears to have been used in the design and analysis of this bridge. The design codes dictate deep beam provisions to account for the effects of struts and ties forming and...
Looking at link of video, thanks JohnRBaker and dold, at start of thread
https://www.youtube.com/watch?v=D_LxF8IjH3s
Unfortunately the video starts a little late to capture start of collapse, rewind and pause at 0 seconds. If video was shot from North, take a look at the North Elevation...
Retensioning the rods, where do I begin, several threads ago I posted a comment to similar to, "I hope FIGG's decision to retention the PT rods in Member 11 went beyond, 'Seems like it was performing better before the rods were detensioned, lets put it back on'". Reading the FIGG employees'...
Vance Wiley, thank you for the thank you.
The Mad Spaniard, thank you, I was hoping someone familiar to the FDOT Specifications and general interpretation would comment.
Both, thanks for the discussion on the FDOT specification topic.
To me, FDOT 440-4.3, is very arbitrary. There is no...
Reviewing FIGG report, Party Submission (last item in NTSB docket), Appendix A, WJE report, full scale tests of member of 11. A few observations come to mind.
It would seem to have been better to have used the Florida aggregates in the in the full scale tests rather than create an adjustment...
Reading thru the FIGG report, I went huh when I hit the part in recommendations where they felt the need to insert some of their own "propaganda" in a technical report. Then I got to the part where they recommended better hard hats may have reduced/prevented injuries and fatalities. This is...
The construction joint, Egad, I still can't believe anyone would have a construction joint at such an angle to the primary axial force in Member 11. Still thinking peer review, ASI, RFI, shop drawing markup, field observation, or something would have changed this from flat across the deck...
It has bothered me, as others have stated, on how the decision to restress the PT bar in Member 11 was made. I would like to think it went beyond, seems like it was working better with the force in the rods, lets put it back on.
A thought I heard many years ago on the safety of a structure...
Consider a vertical pinned end ideal truss, all members including the top and bottom chord are pinned at the joints. Now enforce an outward horizontal deflection at the first interior top node. The truss simply performs a rigid body rotation about the end pin support. Suppose now that the...
As facts have began to come forward, I am interested in what others opinions may be for Code changes.
A few that I have come up, just my opinion, and not all the facts are in.
For ABC or any method of construction that puts the general public at risk, are Construction Phase load factors and...
Here's another thought experiment.
Take a 6" diameter cylinder, place 1% vertical reinforcement, 8-W3.5 wires, you would need to use W4 wire if you want them commonly available deformed, cast the first half with a cold joint at 30 degrees to vertical, (not an exact match, but close, plus I have...
Thanks JRS_87, your post was a little long to requote, no offense is intended.
My basic line of reasoning for the 11/12/deck system is that it is a strut and tie system, looks a lot like the strut and tie method diagrams in the Codes, not so much the shear friction diagrams.
From not quite 40...
Based on Design Documents I have been able to find, not final, and the presumed reinforcement in the members from the Design Drawings, it appears reinforcement shop drawings have not been made available yet (if anyone has I link, perhaps I missed the link in a previous post, that would be very...
First time poster on this thread, thanks to all who gathered information and presented ideas.
A few thoughts, the use of shear friction design requires clamping forces to be developed on the face of the presumed crack. In order for clamping forces to develop at least one side must be free...
