by Erika Merideth
The famous Chrysler building in New York City is undergoing restoration of the elaborate fresco on its ceiling. But just next door, the lesser known Chrysler Center is undergoing even more extensive renovation. The 50-year-old building is being re-clad with a dark blue glass curtainwall which will be placed over the existing white brick exterior. Completion is planned for mid-summer of 1999, but initial challenges in accessing the 66-story building threaten that goal.
The buildings height, coupled with its location on confined city streets made access to exterior walls difficult. In addition, the upper floors of the main tower are set back approximately 20 feet from the lower ten floors. This was seen as a problem at first, but later proved to be beneficial.
The Florida-based company Glassalum, who was contracted to supply and install the curtainwall, decided to evaluate the possibility of mast climbing work platforms. The setback was examined more closely and found to have massive 24-inch steel spandral beams designed to stabilize the main tower in high winds which could safely carry the static loads discharged down the mast.
Atlantic-Heydt Corporation then began to erect the platforms. Steel I-beams were positioned to bridge the spandral beams and provide a base for the mast climbing work platforms. HEK MS 3000 units were used, which feature a wheeled chassis to facilitate movement on sites when used at lower heights. The entire chassis had to be craned to the setback. Five units were required to give the necessary horizontal surface coverage, and there were difficulties in getting these to the setback at the eleventh floor.
It took two nights to crane the chassis, drive units, platforms, mast sections and steel tubing for the anchors up to the setback. After positioning the base trailers, Atlantic-Heydt anchored the masts. Using four epoxy sleeve bolts for each anchor, it tied into the concrete at 20-foot intervals.
Once all this preparation was complete, Glassalum was able to begin its work. The first priority was to attach steel clips for the mullions and transoms that would hold the aluminum-framed glass panels in place. Each clip anchor required diamond drilling a 12-inch diameter hole though the brick veneer and concrete to the steel where the clip was welded in place. This process was hastened by the fact that the adjustable HEK platforms allowed the work to be done from the most convenient position. According to Al Galpine, project manager for Glassalum, the current plan is to first install mullions and transoms to the entire building before fitting the glass panels.
The glass panels will be brought to the eleventh floor setback by an adjacent material lift. The panels will then be wheeled onto the platforms, taken up to the proper elevation and installed at waist level. Galpine estimates each platform will be able to take up sufficient panels for half a days needs. Once the main tower is completed, the HEK platforms will be brought down and used for the lower ten stories.
A few companies in the glass industry will play a role in the process to house the Declaration of Independence, the Constitution of the United States and the Bill of Rights in new cases as part of the imminent five-year project to renovate the National Archives. Archivists have long expressed concern that the current display arrangement is inadequate for the long-term preservation of the documents, which have become fragile from rough handling and exposure to damaging light in the past.
The current display, designed in 1952, seals the documents completely from outside intervention by means of a lite of glass that presses against the parchment. This has prevented archivists from physical examination of the documents or contact checks for possible deterioration. Although the actual documents are in no immediate danger, it was recently discovered that the glass panels which touch the documents are deteriorating. Experts have detected crystals, droplets and surface fissures that indicate deterioration of the glass. This discovery stimulated the decision to build new cases.
The new display case, developed by the National Institute of Standards and Technology in conjunction with Heery International, is a titanium, aluminum and tempered glass case which keeps the actual documents from touching the glass cover and provides better humidity control. The project, including research, design and construction of seven display cases and two prototypes will cost $4.8 million and be covered by congressional appropriations and the Pew Charitable Trusts, according to Archives spokeswoman Susan Cooper. New aspects will include the anodization of all metal surfaces to decrease oxidation, pressure sensors, infrared and laser spectroscopy, temperature and humidity gauges and a glass panel 3/8-inch thick which may include anti-reflective coating. The documents will be placed on aluminum platforms and held in place with clips, allowing them to rest inside the cases without coming into contact with the glass.
According to Rick Judson, project manager for the new display cases, the design team has not yet named which company it will contract to provide the glass or administer the coating, but Solutia Inc. has been chosen to apply the PVB interlayer. In addition, Pilkington LOF has been asked to provide technical advice, specifically about what type of glass to use in the cases. Installation is planned to begin in 2001 and will continue for two years.
Erika Meredith is an editorial intern for USGlass magazine.
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