Climbing above 800 feet
By Euan Youdale16 September 2009
A tower crane company in Canada has erected three large luffing jib towers, two of which will be climbed to a final height of more than 800 feet (244 m) using tie-ins more than 60 feet (18 m) long.
All three cranes erected on the Calgary, Alberta site in July are Terex Comedil CTL630 luffers from Oxford Builders, the tower crane division of EllisDon Construction.
The building's structure is steel with a concrete core. "The cranes need to have four sets of large tie-ins, with struts in excess of 60 feet long," explains Mike Demelo, vice president, equipment, EllisDon Construction. "After each crane is climbed and has its four sets of large tie-in struts, the bottom set will be cycled to the top and a small set will be inserted into the structural steel," Demelo continues.