Skidsteers and mini-excavators are frequently used in top-down demolition to dismantle multi-storey buildings floor by floor.
But it’s a delicate operation which is, by necessity, carried out at height. The safety risks are clear – and machines have been known to disappear over the edge of the building, along with their operator.
As recently as January 2020, demolition contractor McGee was fined £500,000 following the death of an excavator operator who was killed when his machine fell through a concrete floor during a demolition project in central London.
So if you can do it without putting a real live human being in the operator’s cab, so much the better.
This is the thinking behind a decision by Kings Langley-based BooBoo Plant Hire to invest in a new remote-control Bobcat S450 skidsteer loader for use on a job in north London for demolition specialist Erith.
The project involves the top-down demolition of the five-storey Waterlowe Building, a former wing of the Whittington Hospital in Upper Holloway.
Originally conceived as a job suitable for a high-reach excavator, the site’s extreme lack of space demanded a reassessment. With live hospital buildings at the rear, a primary school to one side, residential property to the other and the busy Highgate Hill passing directly past the front, Erith opted instead to use compact equipment to nibble the building down.
Instead of shrouding the building in scaffolding, Erith used its excavator to position a debris shield alongside the active face while a couple of 8.5-tonne Bobcat E85 excavators tackled the concrete frame with boom-mounted breakers and munchers.
While these machines broke out the concrete, the remote-control S450 skidsteer removed the debris. All three machines, plus an S70 skidsteer, are recent purchases which BooBoo Plant Hire ordered specially for this project.
The two E85 units have specially-modified hydraulics that allow them to operate a Kinshofer MQP-25 jaw crusher and large hydraulic breakers. Despite the use of relatively large attachments, the E85 machines still maintained the low ground-bearing pressures required for working safely on the floors of the building.
The S450 skidsteer is the first remotely-controlled Bobcat machine to appear on a UK site. Supplied by Essex-based distributor Bobcat of London, the machine is a conventional cab-equipped skidsteer fitted with a purpose-designed Bobcat remote-control system.
This system is designed to be fitted and demounted quickly and easily. The manufacturer says it takes just minutes to convert the skidsteer to complete remote control.
This means the operator can leave the cab and take up a safe position from which to continue working. In the confined spaces of top-down demolition, the remote-control system removes the operator from dangers such as rebar penetrating the cab space as well as dust inhalation and the effects of vibration and noise in the cab.
Furthermore the operator, besides being taken out of harm’s way, can view the workface from the best vantage-point. The system is compatible with any Bobcat skidsteer, compact track or all- wheel steer loader equipped with the company’s selectable joystick controls.
BooBoo’s owner, Harry Allen, says: “Maintaining maximum safety is paramount. I believe remote control is the way to go in the future in our industry – it’s a no-brainer really.
“As well as increased safety, the remote control saves costs by removing the need for a banksman as a lookout for the machine.”
A banksman is a prerequisite on many sites, especially where space is tight and there is a risk of machines coming into contact with people.
Such is Allen’s enthusiasm for remote operation that he has set up a new company to market the advantages of this technology. The new business, dubbed Lobotics, “will specialise in robotic and automatic solutions such as the remote-control loaders for work on our sites throughout the UK”, he says.
This article was first published in the April 2020 issue of The Construction Index Magazine