Crane Institute of America

Know Your Ground Conditions

A crawler crane erecting wind turbines in Canada last fall turned over while traveling from one to another. Witnesses reported “The crane was moving over the wet and uneven ground when the tracks appear to have sunk at the back, causing the crane to overturn backward.”

Crane over at Canadian wind farm

Cranes must be set up and travel on firm, level ground. Ground conditions are even more critical with long boom cranes like this one, which had 120 meters (about 394 feet) of boom.

It is not surprising that this crane sunk at the rear, since it was in heavy lift configuration where counterweights range from 250,000 to one million pounds along with the weight of the mast mounted to the rear. It is doubtful that the manufacturer of the crane approved traveling in this configuration, but if they did they would specify firm level ground throughout the route of travel.

Thankfully no one was injured in this incident. This story and photos originally appeared on Heavy Lift News.