The Function of Tower Cranes in the Construction of High-Rise Buildings

Any city’s skyline will almost always include a few tower cranes, which are among the largest pieces of construction equipment. Construction companies utilize tower cranes to carry heavy materials like steel and concrete. Large objects like acetylene torches, motors, and generators are also transported using tower cranes.

Because tower cranes are so little in comparison to high-rise buildings, their lifting power is commonly overestimated. How long will the tower crane be able to stay upright without tipping over? How is it possible to raise such a large amount of weight? Is the crane getting taller as the structure gets taller? The basic principles of tower cranes and their functionality will be covered in this article.

Tower Crane Parts

The base, the mast or tower, and the slewing unit are the three primary components of a tower crane.

THE BASE: The crane’s major support is the base. It is supported by a huge concrete foundation that bears the full weight of the structure.

TOWER: The supporting structure that connects the mast to the base determines how tall the crane is. The crane’s strength comes from a huge triangulated lattice structure on the mast.

SLEWING UNIT: The slewing unit, which is attached to the top of the mast and allows the crane to spin around its axis, comprises a gear and motor. The slewing unit, on the other hand, is made up of three pieces.

  • A horizontal device that carries the load and has a trolley along the length of it to move the weight in and out.
  • The load-lifting motor is held by the machinery arm, which is a shorter horizontal piece. To maintain balance, it also has electronic controls, a cable drum, and concrete counterweights.
  • Operator’s cabin: This is the area where the crane operator controls all of the crane’s functions.

Tower Crane Specifications

The following are the parameters of a typical tower crane, but note that they vary based on the type and manufacturer:

  • 265 feet (80 meters) is the maximum unsupported height. Because the building rises around the crane, it may reach greater heights when attached to it.
  • 230 feet (70 meters) is the maximum reach.
  • Lifting capacity: 19.8 tons (18 metric tons)
  • 20 tons or 16.3 metric tons of counterweights

maximum load is 18 metric tons, however, when the load is at the end of the job, it can’t lift that much weight. The more weight the crane can safely lift, the closer the load is to the mast. To avoid overloading, operators have two limit switches: a maximum load switch to keep the crane under 18 metric tons, and a maximum moment switches to safeguard the crane from the load’s bending force. Weather monitoring is critical on construction sites, especially when tower cranes are in use. A strong gust of wind can cause the weight and structure to become unstable, resulting in a collapse. Weather forecasts should be checked often by project management, and lifting activities should be avoided when the weather is bad. A weather monitoring system installed at the project sites can alert project managers to harmful wind conditions that aren’t predicted.

Support System for Tower Cranes

When looking at a tower crane, one of the first things that come to mind is whether or not these buildings are stable. The tower crane’s stability is influenced by a number of factors. The concrete pad is a foundation that was built by the building company several weeks before the crane arrived. The pad’s typical dimensions are 30x30x4 feet (10x10x1.3 meters) and it weighs roughly 400,000 pounds. The crane’s base is supported by large anchor bolts that are deeply embedded in the concrete pad.

Tower cranes are transported in sections to construction sites and then assembled on-site. The jib and the machinery section are assembled by qualified installers, and these horizontal pieces are then positioned on the mast, which is initially just 40 feet tall.

mobile crane is used to place the counterweights once the assembly is complete. The pole rises from the concrete pad and, thanks to its triangulated structure, remains upright. The crew attaches parts to the mast with a climbing frame to raise the crane height:

To balance the counterweight, a weight is suspended from the job.

The slewing device is separated from the top of the mast and pushed up 20 feet by hydraulic rams in the top climber.

The crane operator lifts another 20-foot mast component into the gap, which is subsequently fastened in place.

These steps must be repeated until the required height is reached. When it’s time to remove the tower crane from the construction site, it disassembles its own mast and the remainder is disassembled by smaller cranes.

Source; ny-engineers