So we know it isn’t from financing, so why couldn’t they build a decent tunnel to begin with?
“Hub drivers’ nightmares will last for “months,” Gov. Mitt Romney said yesterday, announcing tests of epoxy-anchored bolts in the Interstate 90 network have revealed a “systemic failure” of the ceiling suspension system that will require millions of dollars in time-consuming repairs.
As the tally of defects continues to mount, Romney said problems in the three-year-old tunnel system are far worse than first imagined, with ceiling supports pulling away in hundreds of locations and engineers contemplating a complete replacement of all 696 epoxy-bolted fixtures.
State and federal investigators have conducted 18 “pull tests” on epoxy-fastened bolts in locations throughout the I-90 Seaport connector tunnel, and found that the epoxy-bolt failures are spread throughout all tunnel lanes east and west, Romney said yesterday.
Will we ever find out the extent of the graft and construction shortcuts taken?
We covered the initial accident here.
“So we know it isn’t from financing, so why couldn’t they build a decent tunnel to begin with?” – – Because it’s Massachusetts. They keep re-electing Kerry and Kennedy…what do you expect? Results? 🙂
Not bad for a $2.5 billion dollar project that has ballooned to over $15 billion.
but way didnt systematic professional tests reveal this problem with the epoxy bolts?
Contracted worker did not think his work would kill.
Contractor supervisor did not think his work would kill.
State construction inspector did not think his work would kill.
State human resources/ executive management did not think there failure to hire technical competant firms would kill.
I agree with you, Kevin. The problem is, there is not enough oversight in these projects to ensure that the appropriate standards are being met. We supplied some equipment for a project on a military base with 11″ epoxy type anchors. The equipment failed, be we were not called out to look at the failure mode until 4 years after the fact. When we inspected, it was at first very clear that the bolts had been installed improperly due to the presence of epoxy and concrete dust on the outside of the bolts. Further inspection showed that the bolts had been cut/shortened. We began to pull all of the bolts and found one that was only 4.5″ long. Fortunately, this was not a life or death situation.
My guess is that there was a widespread belief that the anchors were overdesigned for the installation, there was a belief that there was no way the panels would come down, and that there were probably union or worksite regulations regarding the frequency of inspection.
The big question to ask regards the necessity of the concrete paneling. Wouldn’t foam or sheet metal have worked just as well? Was there a structural necessity to have big thick concrete panels on the inside of a tunnel? My guess would be that it was not necessary.
Maybe they should sell this road to a foreign country. What a boondoggle.
I just don’t understand why they are suspending THREE TON CONCRETE PANELS from the ceiling over the motorists’ heads. Is that just an aesthetic thing, or do they serve some structural purpose?
Nate –
Excellent analysis.
Rob –
It’s my understanding that the concrete panels form a sort of ductwork for the ventilation system. But why concrete and not lightweight metal, indeed?
#3 –
Are you still going to be carrying on your one-note whine after your side loses the 2008 elections?
Being from California, I often wonder about failures that will show up in the next big quake. Every time there is a major quake in others parts of the world that result in a lot of deaths, they talk about our high safety standards. But I can’t help but think about how many shortcuts and payoffs were done by greedy developers to bypass those standards.
My guess is, a bunch of engineers and contractors just got long term jobs in Saudi Arabia or some other country without extradition laws.
In a system like this aren’t bolts and concrete sections suppose to be the load bearing components with the epoxy there to stabilize the bolt in the material? Or is there some epoxy that is suppose to acceptable for load bearing applications?
Ballenger – The epoxy is supposed to bear the load. For the bolt to fail, the concrete should fail. If the epoxy is weaker than any other material, all loading characteristics must be based on the epoxy. However, if the bond between the concrete and epoxy is not there, there is no strength to the bolt system. As a result, your best guess as to the strength of the bolt system is that it will not take any load.
Kevin – It is impractical to test every bolt, due to the number of bolts involved. The key to engineering is to anticipate failures and to make a system that will not fail when marginalized. Ideally, the engineer writes in testing standards that make use of statistics to determine the likelihood of bolt failure. You make sure that 95-99% of your bolts will meet load (statistically). If they fall outside of that range, you fail the tested section and require rework. Then you design the system so that only 50% of the bolts will be required to take the anticipated loads.
Ron Larsen – You would be surprised at how much better our standards are than elsewhere. The same grift shows up across the world, but we punish the guilty (unless they “die of a heart attack” prior to sentencing). Engineers design to accomodate some problems, but obviously there are still failures, albeit much more rare. We could still design and build the greatest structures/railways/bridges in the world, but are continually being limited by environmental impact statements, unclear regulations, and overly confrontational relationships between Owner, Contractor, and Engineer.
Maybe the cost and the failure both have the same problem. It used to be the engineer who called the shots on a job and he had his reputation on the line, success or failure either made or broke you, so you didn’t allow for failure. Now there is over site, with over site, and then there is over site. All of these overseers get paid and no one needs to worry that their career will be distroyed by a mistake that someone else should have caught. How about every level that didn’t catch the error or errors give back the money they made on the job that had anything to do with it happening, and don’t forget the lawyers who drew up the contracts with a few million disclaimers, nor the ones who will make out like bandits on the fallout from it. While were at it maybe we should include every tax payer who wants the moon but thinks someone else should pay for it. Our press who seem to love to tell us about every wrong after the fact, but never seem to really discouver anything before it happens. Or the elected offical that loves to note the funding of projects that are not well thought out in advance. The idiot that thinks his party would do a better job should be at the top of my list. Make it simple one guy is in charge and it is real its his neck if it is wrong, period. #1 it would never get built, #2 nobody would be paying for it.
Was the Engineer expecting un re-enforced compacted soil fill to react as if it were solid competent rock ? Was it a friable bedrock which whould have had a greater depth—lenght of surface area exposed for gripping—-against which to secure whatever adhesive/mechanically expansive devices ?
In either case to me it sounds like a poorly selected system !
Why could not shotcrete have been used—-it could be placed w/ accelerator and then its structural strength could be utilized w/in 24 hours of its placement ? In such an application the concrete could be serve as a load-bearing arch not just dead weight hanging from a ceiling—-air-slacking of fill/incompetent rock could be prevented by its thus enclosing envelope !
This seems so obvious that it makes me wonder who did they have in charge of this project—-such measures are in common use.
Hanging heavy concrete overhead and then placing shallow epoxy bolts into it actually increases the load if there is no holding power to begin with ! I would be equally effective to paint the conrete panels with lead paint !
It just seems so stupid to me.
16 years in mining industry followedby
21 years as special inspector