(Hebrew)
תכנן מבעוד מועד – ותמנע מבעיות בחלק חשוב מהפרויקט
As is well known, the planning stage is the most critical phase of any construction project. This principle applies equally to the planning and placement of tower cranes on construction sites. The process of planning crane placement is often carried out by the site manager or project manager. In projects involving the excavation of an underground parking garage, tower cranes are typically positioned early in the project, during the excavation and shoring stages. This early placement allows the crane to be utilized during the pouring of basement floors, providing a significant time and efficiency advantage.
Even in projects without an underground parking structure, tower cranes are essential for concrete pours, and therefore, in most cases, the crane will be erected within one to three months of receiving the building permit and commencing construction. It is crucial to plan ahead, carefully considering the crane’s location, jib length, working height, and the weights required for lifting.
There are two primary methods for establishing a tower crane foundation on-site (with other methods also available): the first option is a static base, often referred to as a “chassis,” and the second is a foundation anchor. Anchoring the crane using a foundation anchor provides a space-saving advantage on the construction site, as the only element visible above ground is the crane’s mast, which occupies minimal space. In contrast, a crane positioned on a static base may require a footprint of approximately 5.5 meters by 5.5 meters for cranes up to 56 meters in height. For taller cranes, the base could require dimensions of 7 meters by 7 meters or even larger, up to 10 meters by 10 meters.
In most projects involving underground parking, it is easier and more practical to anchor the crane to a foundation placed in the basement floor, as this approach saves space and simplifies operations on the construction site. It’s important to note that planning the foundation and anchor placement is often integrated into the planning of the raft foundation and basement floor, requiring early consideration.
In projects where sufficient space is available, many site managers prefer using a static base (“chassis”) to reduce the costs associated with casting and reinforcing the anchor. However, this is only feasible if there is enough available space on-site for such a base. In conclusion, there is no definitive “right or wrong” method for crane foundation placement; each case is unique. However, it is crucial to plan the tower crane foundation well in advance to avoid mistakes that could impact the crane’s working radius and lifting capacity, ultimately affecting the efficiency of crane operations.
When considering the placement of a tower crane on a construction site, many factors must be taken into account, such as whether the crane needs to be raised or lowered (especially in tall buildings), whether it should be tied or anchored to the building, and the location of the staging area where elements like walls, concrete buckets, and formwork are loaded. Additionally, consideration must be given to the ease of assembling the crane, including its transportation and safe, efficient assembly on-site, as well as its disassembly at the end of the project.
The placement of overlapping tower cranes on a construction site, as well as on adjacent sites, is a central aspect of the work performed by experts and professionals in the crane industry. A lack of knowledge in this area can lead to serious mistakes and potential damage. This critical aspect of crane operations has led to the development of comprehensive regulations, including the Safety at Work (Tower Cranes) Regulations of 1966, as well as the Ministry of Labor’s directive – “Guidelines for the Placement and Operation of Tower Cranes in Extreme Conditions,” Directive No. 567226, published on February 1, 2017.
Regulations in this field have evolved alongside technology, now recognizing the importance of smart tower crane restrictions—systems designed to prevent collisions between cranes and limit crane operations in hazardous areas outside the site’s boundaries, as well as within the shared working radius of two or more cranes on-site.
To summarize, early planning is essential when placing tower cranes on a construction site. Proper planning ensures efficiency, safety, and cost-effectiveness while helping to avoid mistakes and unnecessary expenses. RMA is your trusted partner for tower crane rental, sales, and technical services, ensuring that your project runs smoothly and safely from start to finish.
Hebrew