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School'S Out On Dust Control


One of the United Kingdom's leading demolition firms removed 20 buildings from the former University of East London campus without a single dust complaint,

One of the United Kingdom's leading demolition firms removed 20 buildings from the former University of East London campus without a single dust complaint, despite the extremely brittle, old concrete and close proximity to occupied structures. The year-long demolition effort made way for more than 1,000 new homes.

Company officials described the project as delicate demolition work. It required that some of the buildings be surgically separated, with one portion being removed and the other remaining for re-use or renovation. ìWe literally had to cut away adjoining structures, demolishing some parts and leaving others intact,î says company director Tom Bishop.

Syd Bishop and Sons, demolition contractors since 1929, specializes in commercial, industrial and residential operations, tower-block demolition, industrial complexes, gas installations, bridges, and a broad range of large and small structures. The firm operates a licensed waste-transfer station that includes an extensive materials recycling facility to recover all types of construction material, even providing customers with documentation on volumes of waste recycled and its ultimate fate.

In addition to the sheer magnitude of the job, part of Bishop's challenge was containing the sizable volume of dust that was sure to be generated by the firm's activities; this was cited as a concern during planning stages. According to Bishop, the aging concrete was so fragile that cab windows on some of the company's equipment had to be protected with screens to prevent breakage from flying chips.

As if the aging structures and close-order demolition work weren't enough, Bishop's crews also were faced with some major utility-related challenges.

ìThere were three electrical sub-stations on the site, one of which was still in use,î Bishop says. ìThe site was also crisscrossed with gas lines, and no one seemed quite sure of their exact location. Some of the gas mains never had meters, and there was no easy way to cut them off. In the end, they had to be sealed from outside the perimeter of the site. The process took months to complete.î

Covering an area of about 10 hectares (nearly 25 acres), demolition of the former University of East London started with soft-strip and asbestos-removal programs at the beginning of the year. The company then called on its extensive fleet of demolition excavators including a Hitachi ZX600 equipped with a 36-meter boom and a ZX400 outfitted with a 24-meter boom. Both units had Verachtert VT pulverizers.

To manage surface dust and airborne particles, the company used Dust Boss, a misting system from Dust Control Technology.

A Hitachi ZX470 equipped with 4-cubic-meter bucket was employed to dig out foundations, and the reinforced concrete was broken down by a ZX280 with a Komac hammer and processed by an Extec C-12 crusher. All of the debris was retained on location for processing and potential re-use.

ìThe recycled material was reduced to 25 mm (about 1-inch minus) and stocked for piling mats and sub-base for the new development,î Bishop says. Any waste that didn't have a use on site was transported to the company's main recycling facilities at Longfield. There, it was separated by picking stations, water baths and various automated techniques to minimize the amount of waste going to the landfill.

Construction is scheduled to commence later this month on what will ultimately be known as Academy Central, in time for a hand over to a joint-venture company comprised of Taylor Wimpley PLC and the London & Quadrant Housing Trust.

ìThis has been a remarkably well-organized project, and the client is delighted,î Bishop says. ìDespite the problems with the remaining utility infrastructure and initial concerns over the delicate nature of some of the demolition work, everything has run according to plan and there have been no problems or significant setbacks.î

Article provided by Dust Control Technology.