If you’re in the demolition business, you will surely relate to this festive message from C&D Consultancy:
Today workers began the monumental task of demolishing the K-25 Building at the East Tennessee Technology Park Heritage Center (ETTP), the first facility ever built to enrich uranium using the gaseous diffusion process and, in its day, the world’s largest building under one roof.
“This is a visible sign of progress by the Environmental Management Program to deliver results in Oak Ridge as we begin safely demolishing this massive building,” said Inés Triay, Acting Assistant Secretary for Environmental Management for the Department of Energy (DOE).
Constructed in 1944, as part of the Manhattan Project to develop the first atomic weapon, the massive structure enriched uranium for defense and commercial nuclear power uses until it was shut down in 1964, when more modern facilities at the Oak Ridge site and sites in Kentucky and Ohio replaced the K-25 facility. All uranium enrichment activities at the Oak Ridge site were ceased in 1985.
The U-shaped building covers 17 hectares under one roof, and contains 540 stages of gaseous diffusion and associated auxiliary equipment. Each stage consists of a converter, two compressors, two compressor motors, and associated piping. The building contains more than 650 kilometres of piping alone.
“The workers on the project have diligently prepared the building to be demolition ready, and today we see the results of this extensive planning and commitment to undertake this job in a safe manner,” said Gerald Boyd, Manager of DOE’s Oak Ridge Office.
Activities undertaken to prepare the K-25 Building for demolition include: process system stabilization by injecting a foam material into the equipment and piping to immobilize residual low levels of uranium that may remain in the systems; removal and segmentation of high-risk components; removal of transite panels; and shipment of some equipment off site for disposal. Measures have also been taken to improve the safety of workers, including the installation of nets and barriers to add protection from falling debris.
The building’s demolition is part of DOE’s long-term reindustrialisation strategy at the site, which includes demolishing old, contaminated, and unsafe facilities and reclaiming the property for future use as part of a private sector industrial park now known as Heritage Center. This initiative includes the reuse of some of the more modern, uncontaminated facilities at the site. Many older facilities, such as the K-25 Building, are not fit for reuse and pose potential long-term environmental and safety problems and are therefore being demolished.
The demolition is being accomplished by DOE environmental cleanup contractor Bechtel Jacobs Co. LLC, whose president and general manager, Paul Divjak, said it has taken a long time and a lot of hard work to get to this point, but noted that the job is just beginning and “we must continue to focus on doing this very hazardous work safely.”
The west wing of the building is scheduled to be completely demolished by the end of 2010. The entire facility is scheduled to be demolished with all waste disposed by the end of 2011. Most of the waste from the demolition is being taken to the Environmental Management Waste Management Facility on DOE’s Oak Ridge Reservation for disposal.
The Pectel Group is recognised as a highly capable service provider within the asbestos removal industry, and this enables the company to undertake a wide range of projects. The Pectel Group has evolved into a business that manages the removal of a range of other hazards, such as lead and radiological, as well as chemical and biological contamination.
The former business of the Pectel Group will operate as a division of Keltbray Limited under the trading name of Pectel. Keltbray Limited is in contact with Pectel Group clients and will complete all current contracts, and look forward to expanding the business with the support and resources the Keltbray Group can provide.
Keltbray Group Managing Director Brendan Kerr commented: “To continue the successful growth of the Group, Keltbray has begun a process of change through our investment in the business and in people, and capitalising on opportunities to acquire assets that provide an opening for developing the business in these challenging times; our aim is to grow Keltbray to provide a wide-ranging nationwide service. We are delighted therefore to secure the immediate future of the Pectel business by retaining the current 250 employees to ensure there is continuity in delivery, and that the transfer of ownership is a seamless one for employees and importantly clients.”
Having written on the subject of construction and demolition for the best part of a quarter of a century, you’d think I had seen it all by now. And yet, the innovation, inventiveness and utter lunacy of some demolition work can still throw up the occasional surprise:
Necessity is the mother of invention, according to the old adage. So when Pittsburgh officials were faced with a crumbling car park filled with vehicles, they turned to the inventiveness of the demolition world for an answer. And the solution came in the shape of a high reach excavator equipped with a grab which literally tore the cars from the unstable building.
For the full story and photos, please click here.
Read the full story here.
One of the judges at the 2009 Demolition Awards will be John Woodward, newly-elected vice-president of the Institute of Demolition Engineers. In this exclusive interview, Demolition News speaks to Woodward about his part in these exciting awards:
The international trade magazine Demolition & Recycling International (D&Ri) recently announced plans to host the first-ever award ceremony to recognise the work of demolition professionals the world over.
In this exclusive podcast, D&Ri editor Lindsay Gale – the driving force behind the awards – highlights his hopes and aims for the Demolition Awards:
Nice video showing Welsh contractor Cuddy Demolition & Dismantling despatching derelict flats at Briery Hill, Ebbw Vale.
The multi-span reinforced concrete viaduct at Torano, about 100 km east of the Italian capital Rome, is a major structure on the main E80/A24/A25 Autostrada crossing central Italy. The Viadotto Fiume Salto was opened in the late 1960s, but the use of de-icing salts during winter months has since caused considerable calcium chloride damage to the structure forcing the Italian Highways Authority and the Autostrada di Parchi’s owner Toto S.p.a. to carryout extensive repairs. The renovation, funded by revenue from tolls, is expected to cost around €5M and is focusing on the piers and main joints in the concrete deck using the high pressure water jetting technique of hydrodemolition to remove the calcium chloride infected concrete.
Specialist hydrodemolition contractor C.P.L. 2000 S.r.l., in joint venture with Edil C.R.R. and Global Klima S.r.l. and working for Toto, is using a Conjet 322 Robot hydrodemolition machine and Conjet Powerpack bought specifically for the repair from Conjet’s sole Italian dealer Roald di Codecasa & C.s.n.c based in Milan. “This is a major bridge repair project and hydrodemolition with the Conjet Robot is the only method of removing the damaged concrete,” says C.P.L. 2000 S.r.l president Angelino Rinaldi. “Using very high pressure jets of water to remove only the poor concrete does not cause any damaged to the good concrete left behind and if necessary it also takes away concrete from below the reinforcement, which is also cleaned of any rust. Using breakers would have taken so much longer and also caused damage to the good concrete left behind. Hydrodemolition with the Conjet Robot also has the advantage of producing a very rough surface, which gives a good bond for the new concrete to key onto.”
The viaduct carries the busy dual two lane E80/A24 Autostrada across a narrow valley skirting to the south of Torano and just before the E80/A24 forks northeast towards L’Aquila and southeast onto the A25 to Pescara. The bridge deck is supported on 12 pairs of reinforced concrete hollow piers up to 40 m high and spaced at intervals of about 42 m across the valley. The individual piers are spaced at about 11 m centres and each one is topped with its own transverse crosshead, which in turn supports longitudinal precast concrete beams for each carriageway deck.
The main focus of the hydrodemolition repair is on the octagonal shaped piers and their crossheads where the de-icing salt has leaked down from the deck above. The calcium chloride attack on the concrete is inconsistent with a patchwork of damaged areas over the surface of the 24 piers totalling about 380 m2. In many instances the de-icing salt has seeped deep into the concrete and the resulting corrosion of the reinforcement has pushed the concrete off and exposed the reinforcing to further corrosion from the elements. C.P.L. 2000 S.r.l concentrates on one pair of piers at a time and successfully uses a special purpose built rack and pinion climbing platform designed and built by Safi, which gives the Conjet 322 Robot unrestricted working access to all faces on each set of piers. The Conjet 322 Robot is connected to a Conjet Powerpack delivering clean fresh water at a pressure of about 1,300 bar and flow of 200 litres/min and is removing concrete generally to a depth of 30mm to 130mm. In some instances maximum removal depth has been as high as 180 mm, but the average on the project has been between 70 mm to 80 mm. “We bought the Conjet 322 Robot specifically for this project and has been operated by Yamadu Konate and Vittorio Triuzzo. The 322 has been a very good machine and I can’t see how we could have done the job without it,” says Angelino Rinaldi.
After C.P.L. 2000 S.r.l has finished concrete removal from one set of piers the company moves onto the next pair using a separate, but identical Safi working platform. Another contractor in the joint venture then follows on using the first platform to spray steel fibre reinforced concrete on the patches, which are levelled and float finished by hand. The entire sequence is repeated on all 12 pairs of piers. C.P.L. 2000 S.r.l is also using hydrodemolition with hand lances to remove the damaged concrete from the main joints on the bridge deck and also directly underneath the longitudinal beams supporting the deck.
Conjet was involved at the early stage of the project and assisted CPL 2000 S.r.l. in selecting the right type of platform they would need on the tall piers. Conjet considered the space the robot would require to work in an unrestricted manner and maintain high production during the concrete removal process. CPL 2000 S.r.l. is using three platforms and after concrete removal with the Conjet Robot they are also used for the placement of fresh concrete.
To complete the concrete restoration the repaired structure will be finished off with a final coating of protective paint to prevent possible future attack from de-icing salt. The repairs started in June 2007 with the hydrodemolition following on three months later in September. The project shut down during the winter months from December to March and restarted in spring of 2008 and finished on schedule at the end of November.