Big dig fails again

no, i am not...

just received this breaking news alert in my in-box:

Quote:

Governor Mitt Romney today said he is filing emergency legislation that would give him control of inspections in the Big Dig tunnel where cement ceiling panels collapsed, killing a motorist, and the ultimate decision on reopening the tunnel.

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Some 250 (more or less) bolts need to be either replaced or checked more closely. Tunnels will be closed indefinitely. The fallen panel was not in the section of tunnel with the worst flaw-count. Our atty Gen is starting a criminal investigation. The chairman of the MA TPK refuses to step down.

Phew. What a mess.

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My feeling is that the entire design, which employs minimally safe hanging panels, is a mess. Installation has obviously been substandard, so that will drag in almost everyone in a major lawsuit.

Wasnt there anyone who was hired to do a QA of the original design plans? Any reasonably competent foundation geotech would have had big problems with relying on tiebacks alone.

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I heard this on the radio, so I don't have a link. Supposedly 5,000 truckloads of cement that were delivered was old, (if this is the right word)watered-down cement, not meant to be sold. The sellers and the buyers split the difference in cost among themselves. For example if the contract was for $50,000 for the 5,000 truckloads, but the old cement didn't cost close to that, then the difference was split in cash between all involved.

Good times.

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farmerman wrote:

My feeling is that the entire design, which employs minimally safe hanging panels, is a mess. Installation has obviously been substandard, so that will drag in almost everyone in a major lawsuit.

Wasnt there anyone who was hired to do a QA of the original design plans? Any reasonably competent foundation geotech would have had big problems with relying on tiebacks alone.

The design is for the panels to be supported by Steel I-beams with the tiebacks as additional supports to keep the panels centered between the beams. They've been reporting that several of the steel beams were spaced to far apar and/or failed structurally.

The whole thing is a desgin mess. Things were changed several dozen times over the 15 years between the initial design and the actual construction and parts that were built in the early stages weren't reinspected and fixed to comply with the later design changes.

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so there was no independent contractor who was doing the concrete testing, or else that contractor was on the take also.

The insurance claims for this are going to produce cases that our kids will still be trying

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obviously the tiebacks were carrying load. They should only have (as you said) been there to keep the panels in their place and not carry loads. I wonder whether that portion of the panel load tht was supposed to be carried by the steel beams was, in fact, actually vectoring downward and transferred to the tiebacks.

Were the concrete panels cast on the job or brought in from an outside craftsman? They have to be inspected also to see that they werent too brittle and open to fracturing.

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from today's Bahstin Globe --

Probe looks at possible problems with handling epoxy

Investigators are focusing on the possibility that the failure of epoxy caused the ceiling collapse in the Interstate 90 connector tunnel Monday night.

Glue on bolts removed from the tunnel roof near the accident site was brittle and cracked, instead of having the consistency of smooth glass it should have had, according to a source briefed on the state investigation but not authorized to speak publicly. The decayed appearance may be a sign of premature aging.

Investigators are looking at problems Big Dig crews might have had in handling the epoxy, which requires a precise series of steps to get maximum holding power, according to the source.

The industrial-strength epoxy that was supposed to hold up the concrete ceiling is no ordinary glue. Used properly, it's actually stronger than concrete by some measures, and it's widely used in construction all over the world.

Typically, the epoxy comes in two cylinders, one containing resin and the other hardener, that must be mixed to create the glue on the spot. Workers installing the ceiling in the connector tunnel would have drilled holes into the concrete roof of the tunnel, squirted the epoxy ingredients inside, and then inserted a bolt. Once the epoxy had hardened and workers had tested it, they could suspend steel hangers from the bolt assembly, creating the frame that holds up the tunnel's drop ceiling.

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Over 1,000 problems...... and counting......

Quote:

tests show more than 1,100 bolt assemblies that used epoxy and more than 300 other areas in a Big Dig connector tunnel where the ceiling collapsed are unreliable.

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didn't anyone on that site build airplane models as a kid?

sheesh

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no, but they did sniff the glue...

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I gotta fly into Logan Friday night to get home. Should be fun trying to get out of there. Yeash! Maybe I can move my flight to TF Green or Manchester... *sigh*

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good luck fishin!

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I have heard that many people are changing their flying plans to alternate airports. You should be fine if you arrive later in the evening. Actually I found Fridays the lightest traffic of the week any way - unless you start traveling too far south (cape and Newport traffic).

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Response from the construction company that built the big dig

Bechtel strictly adheres to its contracts and the law and takes pride in its national and international work, said company spokesman Michael Kidder . Large government projects like the Big Dig and Hanford are inevitably complicated, he added.
``Good oversight is good business as far as Bechtel is concerned," Kidder said. ``The huge scope of these projects, and some are first of a kind, are bound to cause some wrinkles along the way, and they become lessons learned."

Some wrinkles along the way? Nice way to put it that they killed a woman.

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Linkat wrote:

Response from the construction company that built the big dig

Bechtel strictly adheres to its contracts and the law and takes pride in its national and international work, said company spokesman Michael Kidder . Large government projects like the Big Dig and Hanford are inevitably complicated, he added.
``Good oversight is good business as far as Bechtel is concerned," Kidder said. ``The huge scope of these projects, and some are first of a kind, are bound to cause some wrinkles along the way, and they become lessons learned."

Some wrinkles along the way? Nice way to put it that they killed a woman.

If I were Bechtel, I might havbe used a different word than ADHERES TO...

Also, if good oversight is good for business, NO OVERSIGHT MUST BE GREAT FOR BUSINESS.

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That's tandard consultant speech. When anything tanks a savvy consultant always runs back to the contract terms to see where its weasel words reside.

I had a contractor once who was hired to install about 50 monitor wells so we could sample ground water for dissolved platinum. The contract stated that these wells were to be drilled as "Ground water monitor wells to a depth of approximately 100 feet (For pricing purposes)

Little did my PM realize that they would drill over 70 of the wells as dry holes. They ran back to their contract demanding payment. We tooke em to court and won. The judge took less than a week to reach his decision on the Errors and Omissions part of the contract.

Most consultants hire kids out of school now , in order to be more competitive, so we who hire them must spend a lot more time doing the "Daubert" test and requiring huge insurance buffers.

If I were Bechtel, Id keep my damn mouth shut rather than sending out spinmeisters who dont know squat asbout the consequences of what they say..

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So, they're opening a section of previously closed tunnel to make it easier for those south of the city to get to the airport. I am hoping that this relieves some of the extra traffic which has been going through Boston over the last few weeks.

The airport is set on a built up (man-made) piece of land NE of the city. Previously, there was 2 ways to get there. You had to trek into and through the industrial warehouse ghostland of Charlestown or go through the sumner/calahan tunnel. The tunnel was accessed from the newly sunken interstate which ran through the city. The entrance is on the north side of boston. So, currently, for those south of the city, this meant a crazy drive through Boston to the North End and the old tunnel.

As for me, I live NW of the city and I can't take the mass pike to 93 south, I dunno if I can take 93 south all the way. So, I'll be taking mass avenue (an intown commercial street of ambiguous lane-age) to 93 south of the tunnels. And, I don't even know if I have to. I can't find a good site which has maps of the tunnels, the connectors, etc. They cite 'ramp a' as being open - but 'ramp a' is big-dig-speak -- there's no 'ramp a' sign on the highway. But, I don't want to just drive it and see, because I will be rerouted through boston and that can get hairry.

Annnnnyyyyyway.......

Apparently Mitt Romney feels much better about the fix the techies have come up with to make the panels safer, I wish I felt as confident:

Quote:

To correct the problem, officials designed and installed 23 new ceiling brackets that increased the number of bolts in each connector to five instead of the original four. Romney held one of the new galvanized brackets aloft for the cameras, saying that the new 18-inch supports were also longer than the originals, spreading out the load over a wider piece of steel.

boston.com

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Big dig fails again

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