Chartered Institute of Building Magazine of the Chartered Institute of Building


Photos | ‘Military grade’ explosives demolish quarry structures

19 October 2020
The moment charges on the quarry conveyor belt were detonated

Demolition firm AR Demolition has used “military grade” explosives to bring down structures at a Leicestershire quarry.

The firm used hypersonic “kick and cut” charges to bring down a large screen house at Croft Quarry.

Richard Dolman, CEO of AR Demolition, said he believed the project is the first time such charges have been used in the demolition industry, without the normal pre-weakening activity usually needed to bring a structure down.

Designed by Wiltshire experts Alford Technologies, the kicking and cutting technique brings together two forms of explosive charge.

The quarry screen house coming down

Roland Alford, managing director and son of the company’s founder and chairman Dr Sidney Alford, said: “We used our Dioplex charges to make a hypersonic blade which cuts through steel like butter, eliminating the need to burn and weaken steel beams.

“When combined with the Wallhammer kicking charge to remove the columns, the speed of these military grade munitions means they are relatively easy to control.

“Without the need to use human beings on weakening work, safety is greatly increased. If necessary, the charges can be placed by robots thereby removing the human element completely.”

Dolman said: ““No one has used this technology in UK demolition before. It was a project which has taken considerable forethought and planning and we are delighted with the results.

AR Demolition CEO Richard Dolman

“It’s a major stepping stone for us and, in my view, a huge moment for our industry. The fact that you can bring down buildings by severing steel without pre-weakening is a landmark moment.

“Alford Technologies have been working on these theories for a long time but, until now, there has been typical reticence in our industry to adopt new technologies.

“So I’m pleased to have been able to put the ideas into practice and find new ways of increasing safety in our sector.”

AR Demolition, which is based in Carlton near Market Bosworth, has been working at Croft Quarry since the start of the year after being contracted to complete decommissioning demolition by site owners Aggregate Industries.

The explosives work was part of a joint project to demolish the 1,200-tonne screen house as well as 150 metres of conveyor belts at the bottom of the quarry pit.