It was a long way up to the top of the tower crane!
Lease Crutcher Lewis (LCL), general contractor for the Lane Community College Downtown Campus project, achieved an important milestone this past week when it removed the gigantic tower crane that stood at the center of the jobsite for nearly a year.
Tower cranes are remarkable things. They appear spindly and yet are capable of lifting enormous loads. The manner by which they are erected and disassembled is fascinating. The length of the horizontal jib on the crane used by LCL was so great it could extend to reach beyond each end of the city block-long site.
The Downtown Campus project tower crane was also tall—very tall. So it was with some trepidation that I climbed to the top of the crane on the day before LCL dismantled it. Joining me (with no hint of unease whatsoever) was Mariko Blessing, Associate AIA, my colleague at Robertson/Sherwood/Architects. Riley Allen, one of LCL’s young project engineers, came along with us too for his first trek to the summit of a tower crane.
I don’t remember suffering much from a fear of heights when I was younger. Perhaps it’s because I’m older now and my physical equilibrium isn’t what it once was, but climbing an open ladder 120 feet into the sky was a little unnerving. The fact the tower swayed in the wind just a bit certainly didn’t help matters. I did overcome my anxiety to reach the top (or more precisely to the operator’s cab, located just below the pinnacle of the crane’s mast and above the slewing unit).
The construction scene of the interior courtyard below the tower crane.
We met Lonny, the crane’s affable operator, inside the tight quarters of the cab. He described for us the operation of the crane, including how much the working arm often bows under the strain of its load. The skill necessary to hoist and move heavy material safely was clear.
Lonny also explained the method that would be used to take apart the crane. A combination of loosened connectors and the sequential removal of the jib components would result in a marked lean to the mast even while Lonny and the ironworkers were still on top of the lofty assembly. He made all of this sound so matter of course when the reality must surely be nerve-wracking and demanding of the strictest possible safety procedures.
Disassembly of the tower crane by a mobile crane (June 13, 2012)
The builder’s granting of permission to the architect to ascend the tower crane before its dismantling may never achieve the ritualized status of other construction project customs, such as the topping out ceremony. Nonetheless, Mariko and I approached the event as a commemoration and our conquering of the looming structure as a rite of passage. We’re no longer tower crane greenhorns; we’ve achieved exalted status as tower crane summiteers.