Self-erecting tower cranes or SETCs can boost both productivity and safety in a construction site. But before you can enjoy these benefits, careful planning and preparation are crucial.
A construction site comprises several moving parts, literally and figuratively. Miss out on one crucial detail and you risk delays, or worse, accidents.
For SETCs, one crucial task that should be given ample attention is siting or site preparation.
Outlined here is a breakdown of tasks related to the siting of self-erecting tower cranes that can ensure the optimal operation of this vital heavy equipment while minimizing accidents.
Ensure sufficient clearance for operation
Before the crane is installed and put to use, it is critical to survey the job site and determine the best location for the SETC.
The ideal location should be free from obstructions and provide the crane ample room for movement. There should be sufficient clearance between the SETC and the structures in the job site to avoid impeding heavy equipment movement as well as prevent unnecessary damages and accidents.
You should also ensure that the chosen location for the SETC has enough room for fencing to prevent the entry of unauthorized personnel into the area where the crane is going to be positioned.
Check the ground condition
Stable ground condition is critical for the optimal performance of SETCs. A stable ground can sufficiently and safely absorb pressure from the crane when it is transporting loads. Check with the manufacturer’s recommendations regarding optimal ground conditions. Specifically, you should look for the maximum vertical load and horizontal reactions, specifications of the support pads, and the ground-level pressure for each support pad.
Evaluation of ground conditions should only be performed by competent persons.
But what if the evaluation indicates that the ground cannot fully support the SETC? There are a few measures that can be taken to support both the earth and the crane. Such measures include the use of timber sleepers and concrete pads which help spread the pressure imposed by the crane while transporting loads.
Be aware of overhead hazards
Another critical factor that should be determined before the SETC is erected is overhead hazards. These include power and communication lines and other existing structures in and around the construction site.
Operating near major transportation lines
If your project is being built near major transportation lines like small airports and railways, it is vital to get clearances from the operators of these. Be aware that there may be restrictions imposed that are related to the use of cranes near such facilities, specifically in terms of height and loads.
Operating near existing structures
If the job site is located close to residential or commercial properties, you may have to obtain oversailing rights from the property owners or managers. Getting these rights and informing the tenants and residents of these properties will help you avoid complaints.
Also, be mindful of the SETC manufacturer’s recommendations related to oversailing and leaving the part of the crane over an existing structure.
Ensure there is adequate power supply available
Check with the SETC manufacturer’s recommendations for power supply. Larger cranes require a three-phase power supply while smaller ones can do with a single-phase power supply.
In case there is no available mains supply in the project site, you may use a generator. Just make sure that the generator can provide ample power to the heavy equipment.
Also, it is critical for the cables supplying power to the crane to have the recommended protection, especially from the elements.
Protection from the elements
If your project requires the SETC to be left erected for an extended period, it is necessary to provide lightning protection.
Earth bonding is commonly used to provide protection against lightning. However, it is critical to ensure that there is adequate earth to ensure there is an ample resistance path between the crane’s bottom and the ground.
If the tower happens to be struck by lightning, it should be carefully inspected before operation.
You should also be aware of the manufacturer’s recommendations regarding the operation and out-of-service wind loadings. This will help your personnel anticipate high winds and take the necessary precautions, including dismantling the crane.
Site preparation is a vital task that cannot be overlooked if you want to make optimal use of your chosen self-erecting tower crane. Pay attention to the manufacturer’s recommendations and the tower crane hire firm, if you are hiring one for your project.
Hermann Buchberger is the Founder and CEO of Active Crane Hire (ACH). He’s taken the company from start-up to Industry Leader offering the largest fleet of construction cranes in Australia. ACH launched a new type of crane previously unheard of in the Australian market: electric tower cranes. The company’s infrastructure and associated services now comprise a fleet of trucks and trailers, a crane-rigging team, mobile crane technicians, a fleet of service vehicles, and an extensive range of crane spare parts.