24 Jun The CA/T Documents
The CA/T Documents
According to video footage and documents from the The Central Artery Tunnel (CA/T), there are much more than anchor bolt issues in Boston’s Massive Dig concrete. About 3,600 cubic feet of concrete building utilised contaminated concrete from recycled excavate. There should be an examination into the CA/T documents to verify the chemical properties of the recycled aggregate soil and the concrete tested for corrosion and expansion contaminants.
The gushing and fawning by Boston columnists more than how rapidly Governor Mitt Romney mastered the nuts and bolts of Huge Dig data is frightening. I feel his new located leadership is a diversion. In a slick show of control over the Central Artery Tunnel fiasco, Mitt commands respect with a flick of his magic pointer. The media swoon. It appears like a Boston rendition of Chicago Bechtel as Roxie Hart kept secure and comfy in the lap of master puppeteer Mitt Romney, playing Billy Flynn. Good guy, cute guy, downright lovable when he is home pretending he cares, wonderful song and dance man, but there is much more going on here than screwing in anchor bolts. A lot tougher queries need to have to be asked and investigated by the regional media and by independent safety engineers to assure that no a lot more three-ton ceiling slabs land on commuters or travelers. But, as with any very good magic show, Mitt has all eyes trained on the anchor bolts although he tries to convince the public jury that the genuine fault lies with Matt Amarillo and that Bechtel must be free to just walk out the door.
Just when we believed it was going to be protected to go back in the Central Artery Tunnels in Boston, the Governor let us know that a lot more anchor bolts had been faulty in several lanes of I-90 and maybe in a lot more tunnels. A single of the difficulties with listening to Governor Romney, Turnpike Chair Matt Amarillo or most CA/T predecessors is that they are lawyers and businessmen, not engineers. So take a minute throughout the Magic Mitt Show to pay a visit to the CA/T with my tunnel vision due to the fact something does not smell appropriate. Even though the laser light is dazzling and the hard hat adds such charm. Im not prepared to clear the deck of the Super Scoop barge for a decisive victory photo-op.
Initial, take a genuinely close appear at the failed epoxy holding the anchor bolts that suspend the 3-ton concrete ceiling panels. Right here are some of the straightforward to follow instructions for construction workers regarding epoxy-
Prior to application, all locations must be free of contamination such as waxes, oils, loose concrete, dirt, curing compounds, and so on. Acid etching, followed by correct neutralization and rinsing, is generally acceptable if the concrete is in excellent condition, not contaminated. (emphasis mine).
Drum Roll-Mitts shines a laser light into the dark tunnel and we hear the ooows and ahhhs more than the new, shiny anchor bolts, and a slight of hand trick begins. Will the rabbit now keep in the hole or pop out of the challenging hat?
Wake up. Get rid of your gaze from the anchor bolts and focus on the other finish of the suspension rods inside the ceiling panels themselves. We see a concrete ceiling with newly tightened anchor bolts on the top and steel cable rods embedded in three-ton concrete slabs suspended beneath on the other end of the cable. No steel beams exist in the I-90 connector to develop the desirable steel-bolted-to-steel infrastructure. So any suspended cable will only behave as well as the concrete on either end permits it to behave. If I place an anchor bolt in a wad of silly putty and hang a rod embedded in 5 lbs. of modeling clay from it well its hanging there with a restricted lifespan, I dont care how new the anchor bolt might be.
Anchor bolts will mean quite small if this building mess in downtown Boston is the outcome of mixing contaminated dirt and fill into the composition of the concrete ceiling, walls or floor. Here is how the trick may possibly have been done:
(1) Although most eyes adhere to the light and concentrate on anchor bolts, our current investigation shows that there is a worldwide demand for recycled building merchandise. This demand has enhanced substantially for the duration of the past two decades. The Big Dig produced over four,000 miles and over 11 million cubic feet of dirt in the early digging stages. Most of this dirt and debris was processed for contamination and recycled into the Huge Dig as clay landfill capping material, project backfill and as aggregate (mix) for the tons and tons of concrete required for the project. The miles of added dirt came from the demolition at the airport, the dredging of the harbor floor by the Super Scoop for the Ted Williams Tunnel, the digging of the coffer dam, excavation of miles underneath downtown Boston for the Tip ONeil Tunnel, digging out tunnel entrances, and so on.
In Massive Dig II: Down Under, co-producer Arnie Reisman and I investigated this dirt and decided to stick to the good news. The uncontaminated clay portions of this fill have been going to be utilised to cap Spectacle Island and hundreds of Massachusetts landfills, an proper reuse of heavier clay materials. We have been assured that there was a dirt-testing lab and that all of the contaminated soil was getting correctly distributed and reviewed by the Division of Environmental Protection (DEP). We were handed stacks of literature, interagency agreements concerning contaminated components and many, several press releases about the massive volume of dirt getting tested and processed. Occasionally there was other great news on the disposition of the dirt. There had been mountains of dirt and any disposition was trigger for celebration. After all, any unused dirt was going to price the project and the managers big funds for disposal.
(two) Digging back through my Big Dig supplies I unearthed a 1992 Memorandum of Understanding in between the Division of Environmental Protection and the Massachusetts Highway Division about the contaminated materials in the soil. This addressed the process for oversight and inspections of the dirt for particular chemicals contaminating the soil that are dangerous to humans and wildlife. Of course, those employees at the state DEP who have been overseeing the procedure with the Big Dig have been salaried by the Massachusetts Highway Division and the Central Artery Tunnel Project. We wont even commence to examine that closet. Why? Since right now we are trying to figure out the rabbit in the hat for Mitts Magic Show about the anchor bolts.
(three) For the duration of building, there seemed to be an ongoing safety approach relating to the concrete. Footage in Huge Dig IV: Still Operating contained a segment on the concrete testing method that was overseen by the Joint Venture of Bechtel and the Massachusetts Highway Department. This footage will quickly be accessible at our net web site, exactly where we will also uncover what we think about to be the design modify that is causing continuous leaks in the I-93 tunnel.
This previous winter, a little Big Dig contractor was accused and indicted for allegedly mixing as well a lot old concrete in with new concrete to generate a substandard mix that might be contributing to some leaks in the I-93 tunnel underneath Boston. This was a red flag that something might be NOT O.K. with at least some of the concrete but no a single genuinely noticed.
(four) By seeking meticulously at the Memorandum of Agreement it is apparent that the chemical contaminants in the DEP agreement are not the exact same chemical contaminants that can be dangerous to the strength of the concrete or to the tendency of specific chemical contaminants to corrode embedded steel. When particular chemical compounds are present in the sand and soil used as the aggregate or the mixing soil that is added to cement to make concrete they can weaken or impact other properties of the concrete. These effects may occur more than time and consequently could not be detected making use of temperature and slump tests on the not-however-hardened concrete. The Joint Venture (the state and Bechtel) was required to sample portions of the concrete in all Massive Dig contracts for strength. If the aggregate utilised to make this exact same concrete contained chemical contaminants that do not affect concrete strength, but can corrode steel fittings rapidly how would we know? Effectively, obviously we check the requirements, right? That way we constantly mix in aggregate that does not contaminate the concrete in approaches that can be disastrous.
When I looked for national requirements on chemical contaminants and concrete mix, I identified only an early attempt in Australia (1994-1996) to create such building requirements for recycled material utilized in concrete building. Several more Internet references attested to a lack of the type of precise testing over time that could lead to such standards. Possibly the CA/T was following a set of engineering standards of which I am not aware. Of greatest concern is for the public to be informed about which chemical contaminates can impact the strength and durability of the concrete and which were present in what percentages in the recycled fill employed throughout the CA/T tunnels. It is particularly critical that an independent evaluation team tends to make a thorough investigation of the chemical properties of the recycled aggregate soil used all through the project. This could help to recognize places that can be anticipated to have premature corrosion of steel rods embedded in concrete or that result in the concrete to expand or crumble or leak.
So 12 years of Republican controlled reassurances that the damaging soil was getting disposed of properly failed to clarify to us that the tests had been only for the chemical compounds and soil properties directly dangerous to humans, for example, piles of dirt that contained mercury. The tests and press releases from the CA/T in 1991-1995 did not describe the concentrations of chemical contaminants in fill that could trigger premature collapse of the tunnel ceiling or walls from faulty concrete. We are attempting to get these listed on our net web site at [http://www.polarisproduction.com/big-dig-concrete.html] . We would appreciate hearing from any students, engineers or chemical engineers who can offer clarification on this matter. We will post your info and we will post any established requirements for contaminates utilised in concrete aggregates along with any requirements used by the CA/T in disposition of the dirt back into the Artery construction.
Even though we will continue to investigate this prospective concrete catastrophe and review the documents and tapes at our disposal, somebody with far greater resources, like the mainstream media demands to examine the CA/T deals made with contractors. How much of the previously used dirt and debris from demolition, dredged or excavated material have been every of these contractors required to reuse in their concrete? Was it tested for the road salts and other contaminants that may possibly not be quickly damaging to people and therefore ruled usable by the DEP? Had been those contaminates in enough quantity to pose issues as a concrete aggregate? Does the work to get rid of over four,000 miles of soil via recycling and to save income or make money from disposal of the fill now threaten our lives with weakened or corrosive concrete? Our future could depend upon understanding the nature of these man-produced caverns before the Massive Dig becomes the Big Tomb. Keep in mind, look beyond Mitts Magic Show to see how this rabbit was stuffed into the hole in the first spot.
Subsequent we look at the design alter that could be the principal result in of I-93 tunnel leaks.This one particular modify may well have set in motion an on-going set of issues with downtown leaks in Boston’s Central Artery/Tunnel.
©2006, Dale Orlando