UK tower crane rental company Bennetts Cranes has taken a Raimondi LR 213 luffing jib tower crane to a free standing tower height of 105 metres, which the company claims is the highest freestanding luffing jib crane currently working in the UK.
The crane was initially installed last August at the high rise development in Chelsea Creek, London, at a more typical free standing height of 55 metres. Then last week a team from Bennetts Cranes used a 1,000 tonne All Terrain crane to add further tower sections in order to increase the tower height to 105 metres. The original base tower sections are 4.6 metres square - more than double typical freestanding tower dimensions. The additional 50 metres is a made up of more regular sized tower sections.
There has been a steady trend towards higher freestanding cranes in the UK in recent years, driven by changes in cladding systems which can be obstructed by tower crane ties.
The LR 213 is working alongside Bennetts’ new 18 tonne capacity Raimondi LR 273 luffing jib crane and a 10 tonne Raimondi LRH174 hydraulic luffer. The contractor is St George, part of Berkeley group, which is building a selection of ‘Manhattan’ one, two and three bedroom homes at the site.
Managing director Edward Seager said: “When you double the height of a tower crane, the forces don’t just double, they square, so one of the ways to counteract that is to use a much wider tower base to spread the forces and make it more stable. This base, which is concreted into the ground, is extremely strong and has been brought in specifically for this job. We were pleased to increase the height of the crane to its final height of 105 metres over the Easter weekend, with good weather, enabling us to complete it within two days.”
“Freestanding cranes can provide more flexibility on site, and result in a quicker build time because you don’t need to climb the crane and tie it to the building. There are positives and negatives on both sides, because freestanding cranes are typically more expensive as they need to be reinforced to withstand forces, but the hire time can be reduced with a more efficient build.”