Tower Crane Assembly at 1515 Commonwealth Ave

A red tower crane at 1515 Commonwealth Ave

1515 Comm Ave powers ahead with trade partners East Coast Interiors and North American Crane and Rigging.

The tower crane looms above as walls and trusses are brought into place. Ever wonder how a tower crane is built? The short answer: it builds itself.

The initial structure is assembled by a smaller crane, then extends (in height) by inserting segments into itself – almost like vertebrae in a spinal column.

How is that possible? The top segment of the tower mast (vertical column) inserts in a gap braced by an external segment, effectively “bridging” the opening. The infill segment draws into the mast below the operator’s cab by the jib (the arm extending perpendicular to the tower), then bolts in place. The cab and jib ratchet up to create the next “open segment,” as a new vertebra (segment) is placed in the spinal column (mast). 

Side note: the load on a jib must be strategically placed depending upon its weight when it’s being lifted – so it doesn’t out-balance the crane.

This process repeats until the target height is met. This process called “climbing” is typically done throughout the construction process because the crane grows alongside the high-rise.

As work continues on the condo and rental complexes at 1515 Comm Ave, the tower crane will be a site staple for months to come.

At its final height, the project’s tower crane at the rental complex will be 54 tons, 124 feet tall, and have a load capacity of 15,000 lbs.

Two photos - one selfie by the project engineer and the other of the estimating team on their visit to site

Field Engineer Luke Maglio snaps a shot of the Planning + Cost Engineering team as they visit site earlier this month.