5.7 Tower Cranes
5.7.1 Sitting of Tower Cranes
1) Once a building or structure is finished, a tower crane has to be dismantled – this factor should always be taken into account when deciding its initial position.
2) Special attention should be paid to:
• Gradients : bases for tower cranes (static or rail mounted) must be properly designed and well drained. Manufacturer’s recommendations on the maximum permitted gradient should be strictly observed.
• Proximity hazards : sufficient clear space for the length of the jib involved should always be provided. With other cranes nearby, overlapping of jib can create a special problem – jib and counter jibs might touch and it is essential, therefore, to have a height differential. Great care is equally necessary to avoid ropes fouling and loads being damaged. In such circumstances, operators should be provided with audible warning devices or intercom speech facilities and a priority movement system should be introduced.