EuroWire November 2017

Transatlantic cable

of the structure for potential cracks. At 1,121 feet it will be the tallest building in Philadelphia in the state of Pennsylvania, and the tower is also slated to come No 3 after the skyscrapers of New York and Chicago. John Gattuso, Liberty’s regional director, said that between 35 and 40 possible “indications” of cracking were found in the steel being used to construct the two-storey-high frame that will house the CTC’s lighting and mechanical systems atop the building’s 60 storeys. An inspection of the tower was to include examination of each of the 5,200 welds binding 621 separate pieces of steel being assembled to support the building’s lighting and mechanical equipment. Any cracking is believed to have occurred during the steel’s galvanisation process and is easily repaired, Mr Gattuso told Jacob Adelman of the Philadelphia Inquirer . “This is not rare, but it’s not totally common,” he said. “It’s not a catastrophic issue.” The possible worry-points may be merely surface markings, but any actual cracks that are found can be repaired by drilling holes into the base of the fractures to arrest their growth, Mr Gattuso told Mr Adelman. (“Potential Cracks Found in Frame Atop Comcast’s Rising Tech Tower,” 23 rd August) † Philadelphia-based Comcast Corp is the largest broadcasting and cable television company in the world by revenue. Its plans for the $1.5 billion building include o ces and labs for the rm’s growing workforce of technologists, engineers and software architects, as well as studios for its local NBC and Telemundo a liates and a Four Seasons hotel.

According to Mr Galarza, the dead weight of the girders is 900 tons and their pulling force about 100-110 tons. He said each of the jacks is strong enough to support the entire weight of the girders in the case of catastrophic failure of one of them. Mr Wright, the observer, said that the motion of the jacks – pulling cables connected to the girders – was such a slow, deliberate process that the advance (18 inches at a time) was almost undetectable. A representative of project engineers MNS described the procedure following on the girder launching, with the bridge in position to be jacked up during removal of all the temporary structures it had been riding on. Once it was set back down, the nal business of creating a usable bridge could commence: putting the deck and guardrails on, paving the roadbed, striping. † Crews demolished the old Pfei er Canyon Bridge in March after a landslide caused its support columns to fail. The new span, whose cost is estimated by Caltrans at $24 million, is expected to be commissioned by the New Year.

In Philadelphia, construction of the tallest building in the United States outside New York or Chicago hits a snag

Liberty Property Trust, the builder of the Comcast Technology Center (CTC) tower, in late August paused assembly of the uppermost portion to inspect the steel being used in that part

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November 2017