Building Cranes
The Sacred Heart Hospital building project involved using cranes on the inside of the building as it went up. The building had concrete floors. There was a slight conflict involved with pouring concrete where the crane was set up. The project used a procedure that I found interesting.
A square hole in the concrete floor was left open where the crane was set up. The crane was used to hoist concrete up to each floor. When about three floors had been completed, the crane would lift itself up and reset itself on an unfinished floor. The square openings in the lower floors would be poured using wheel barrows and then the process would start all over again.
(Just to be clear, when I say that the “crane would lift itself up and reset itself on an unfinished floor”, I don’t mean to imply that the piece of machinery was self-aware. It’s just simpler than describing all that the operators did to accomplish the feat.)
As the project proceeded, I wondered what the plan was when the building crane reached the roof top. How would it be removed when all of the access holes were filled with concrete?
One weekend I went by the job site just out of curiosity and found that a huge crane had been transported in and was lying in an ally next to the project. That crane was so large that it took up a whole block in the ally. That crane was just lying there waiting for someone to build it.
The next week the newest crane was assembled and used to lift the building crane off the top of the building and down to the street.
It made sense that the larger crane was transported in a disassembled state. Sometimes when you see large construction sites in a large city you will see a forest of cranes. In the past, crane operators and ground personnel would use hand signals to communicate. Often times a crane operator would sit for long stretches of time waiting for his next lift.
I heard the story of one crane operator that took the National Electric Code book with him up in his crane cab. He studied it during his wait times. He completely read the book, took and passed the required testing, and became a licensed Electrical Administrator. And he knew practically nothing about hands on electrical work.