A wheel of large boom lift working in Market street Manchester, UK, last Wednesday, broke through into a void causing it to tip. Thankfully no one was hurt in the incident – or so we understand.
The lift a 135ft Genie ZX-135/70, from the Quicklift fleet, was fortunately travelling in the fully stowed position when the ground gave way under the wheel, causing it to tilt precariously. Clearly if it this had happened when the machine was fully elevated there would have been a serious likelihood that it would have overturned fully, causing fatalities and a great deal of damage to surrounding property.
The ZX-135 weighs over 21 tonnes on runs on four - effectively solid – poly filled tyres, meaning that each tyre has a minimum weight of more than five tonnes, and in some configurations or circumstances it can be more than 10 tonnes and in exceptional cases as much as 15 tonnes.
So, it is no great surprise that working in a pedestrian precinct, close to a department store, with the wheel that broke though running on ground that would have originally been a pavement/sidewalk would have posed some ground bearing risks. Even if the ground was solid the machine was likely to have cracked the paving slabs, so it is surprising that ground guards were not used.