An object lesson in how demolition SHOULD NOT be carried out

Now here’s something you don’t see everyday; demolition by cannon!

DustBoss equipment controls dust on a mall demolition project in the US capital.

One of the Washington, D.C. area’s most experienced demolition contractors has successfully controlled extensive dust from taking down the old Waterside Mall, a 4-storey, heavily-reinforced concrete structure totaling 111,484 square metres. Crews were able to effectively suppress both surface dust and airborne particles with portable high-performance misting equipment, despite the crowded urban location and close proximity to the local Metro station tunnel entrance — 21 metres from the razed structure — in what has been called a “surgical” demolition project.

Engineers from Wrecking Corporation of America (Alexandria, VA) knew from the outset that the densely populated area and close proximity to remaining structures would require extraordinary precautions. “The Metro station entrance has a way of creating a vacuum,” explained executive VP Terry Anderson. “If the wind is blowing the wrong way, the dust gets sucked right down. The site was also hemmed in on three sides by structures that needed to be preserved, so we had to do a very selective removal, while protecting the entire surrounding area from the nuisance and potential hazard of airborne dust.”

After researching possible solutions, Anderson decided to rent a DustBoss DB-60. As the largest of the suppression designs from Dust Control Technology, the unit atomizes water droplets to the optimum size for particle capture, launching them 60 metres or more with a powerful 18 kW fan that generates nearly 850 cubic metres per minute. With its built-in oscillation, the DB-60 can effectively cover nearly 0.2 hectares with a fine, dust-trapping mist.

The DB-60 is a fully automatic ducted fan design, mounted on a wheeled carriage so it can be easily located to accommodate wind direction or specific work areas. The unit delivers adjustable elevation from 0-50 and a 40 degree oscillation range, providing WCA crews with outstanding coverage.

“The droplet size is critical to effective suppression,” explained Dust Control Technology CEO Edwin Peterson. “Dust particles tend to be in a fairly narrow size range, so the water should be atomized to droplets near that same size for maximum attraction. Our standard models produce droplets from 50-200 microns, but all of our units are designed to be easily customized for targeting specific particle sizes or for cooling applications,” he said. Peterson observed that the nozzles, fan and other components must also be designed to work together for optimum flow, spray angle and delivery pressure to achieve the necessary droplet size, velocity and distribution.
Anderson’s crews run the DB-60 with power from a portable generator and water supplied by a fire hose. A 7.5 kW booster pump elevates water pressure in the DB-60 as high as 200 psi for outstanding particle suppression. It can also be outfitted with a dosing pump to accurately meter odor control additives or surfactants to further enhance binding of dust particles.

WCA began the project in November of 2007, and the old structure did not go easily. “This was one of the more difficult buildings we’ve taken down in some time,” Anderson admitted. He has no explanation for why a decades-old mall was built with 20-inch (51 cm) floor slabs, when the standard is about 23 cm. “We had to fight down every step,” he said. It’s also the largest contiguous building that the company has ever removed.

In addition to the crowded urban environment, the project was complicated by structures that had to be preserved, including a deli attached to the nearby grocery store. Unfortunately, sections of the structure to be demolished were directly on top of it. “We saw cut through the 20-inch slabs of concrete,” Anderson continued. “Then we had to carefully remove all debris, while protecting the integrity of the buildings to remain and controlling the large amounts of dust that were generated by all those activities.”

WCA employed a high-reach excavator for the general demolition work, a 45,359-kg Komatsu PC400 with a 26 metre boom. Kinshofer dedicated shears with 360 degree rotation were used for cutting the extensive amount of reinforcing steel, more than 5,000 tons overall.
Anderson’s crews also made extensive use of a 90-ton truck crane and wrecking ball. “It’s a technology that virtually never breaks down,” he said. “And it leaves a small carbon footprint.” WCA also used a 63,503 kg Caterpillar 365 track-mounted excavator to take down the structures, along with three Hitachi 450 excavators with bucket attachments and four Hitachi 330 excavators with a variety of attachments that included concrete pulverizers and demolition hammers.
WCA performed all concrete crushing and recycling on-site, with an Extec C10 crusher used to process approximately 53,519 cubic metres of material. The crushed product was used for non-structural fill and backfilling.

“By nature, concrete work generates a lot of dust,” Anderson concluded. “We felt we had to take strong measures for control on this project. The DustBoss did such a good job that we decided to purchase the unit,” he added.

C&D offers free football tickets for course bookings

Tipton-based C&D Consultancy is offering FREE football tickets for a series of English Premiership matches at the nearby West Bromwich Albion ground for anyone booking two or more training courses TODAY.

Full details can be found here.

Hits on the Demolition News website hit all-time high

As you are all probably aware, Demolition News is very much a start-up company; we have been posting stories and video content for just a few months and slowly building a community of loyal and occasionally vocal readers.

As a result, we are constantly monitoring the traffic stats on this site, partly to make sure that SOMEONE is reading this stuff but also to gauge what content is popular and what isn’t, so we can improve our offering in the future.

I have just checked our stats for yesterday (thankfully, the analytics are 24 hours out-of-date so I am not tempted to keep checking like I would if they were shown in real-time) and we are pleased to announce that we have just hit an all-time high.

Apparently, yesterday’s combination of a shaky rugby stadium video, the news of Red Rhino’s last-minute rescue, and our damning indictment of the forthcoming SED 2009 exhibition was just the right mixture.

We thank all of you who find the time in your busy days to read this stuff, and for your continued support.

European Demolition Association uses Demolition News to promote spring conference.

Regular readers of Demolition News may have spotted a new sponsor’s advertisement to the left of this article. We are delighted to welcome the European Demolition Association as our latest sponsor and look forward to an ongoing relationship with them in the coming months.

Please also look out for the next (second) edition of the Demolition News magazine which will feature an exclusive interview with EDA president, Yves Camessa.

Prospects for the SED 2009 exhibition are not looking good.

Let me start by saying that I haven’t missed a single SED since 1986. While I was spared the bog that was the Hatfield site, I am a veteran of Whipsnade, Milton Keynes and Rockingham and have seen the show grow and grow. Furthermore, I will be there again this year, camera and notebook in hand.

However, I have some serious concerns about this year’s show, and not all of them are recession-related:

People – For almost as long as I can remember, the show has been in the safe hands of key organisers Mark Bresnahan and Jackie Hanford, a winning pair who traveled the world promoting what remains a parochial show. However, Jackie has taken an early (and well-earned) retirement while Mark has been moved up in the organisation, leaving the day to day running of the show in the hands of a team of relative newcomers just as the industry goes into recession. I have no doubts about the qualifications of the new team but they will have to work incredibly hard to recreate the rapport that Mark and Jackie enjoyed with the industry.

Timing – This is a bad year for exhibitions in many ways. For one thing, the major manufacturers will be putting the majority of their backing and resources into the Intermat show in Paris. Not only will this mean less money to spend at Rockingham, it is also going to give everyone a sneak preview of what new products are (possibly) going to be on show at SED. Furthermore, this is also supposed to be a Hillhead year when, traditionally, some of the larger equipment manufacturers and compressor suppliers bypass SED and keep their powder dry for the quarry industry show a few months later. It’s true that Hillhead HAS been postponed but the presence of Intermat and the shadow cast by Hillhead is likely to impact upon the presence of the larger manufacturers, reducing the pulling power required to attract visitors. And if you’re in any doubt, take a look at the current exhibitor list and see if you can find Caterpillar, JCB, Komatsu, Hitachi and Liebherr among others.

Too big – I do not blame the organisers for seeking to grow the show year on year. Let’s face it, they’re a commercial enterprise and they’re here to make money. However, in doing so I believe they have started to lose sight of what SED is truly all about. Without wishing to sound like a miserable old curmudgeon, I am not alone in missing the old days when SED was about mobile plant, pure and simple. However, with the expansion has come dilution and visitors that do make the trek to Rockingham have to make their way past mobile phone and PPE suppliers to see what kit is on display.

Cutbacks – Backed into a corner by the credit crunch and ensuing recession, the organisers have responded with a somewhat short-sighted, cost-cutting and knee-jerk response. Gone are the SED awards, gone is the well-intentioned but ultimately flawed SED FM radio channel and, if my perceptions are correct, gone is at least some of the show’s external promotion in the trade press.

Venue – Let’s be honest, Rockingham is not a great venue, plain and simple. It lacks the atmosphere of Whipsnade and even Milton Keynes, and while I am not naive enough to believe that anyone goes to SED for the landscape, this is one further detraction from the show.

Economy – Of course, the elephant in the room is the recession, and it is this that will impact upon this year’s show most harshly. Not only will recession-weary manufacturers and dealers be loathe to spend the (considerable amount of) money required to have a presence at the show, the lack of available credit finance is likely to make many visitors think twice about attending – Let’s face it, window shopping with empty pockets quickly loses its appeal.

I am not sounding the death-knell of the show; as I said previously, I will be there when the doors open on the first day. However, I do fear that the usual buzz of conversation may be replaced by the gentle rustle of tumbleweed blowing in the aisles.