|
contents | business | |||||||||
| Hub staircase at the V&A museum relies on DuPont SentryGlas  A new staircase with glass balustrades made of toughened glass laminated together using strong and stiff DuPont SentryGlas interlayer is one of the architectural highlights of the new Daylit Gallery at the Victoria & Albert (V&A) museum in central London. The use of SentryGlas interlayer enabled not only the production of the safe and structurally secure glass panels used to form the balustrade, but also helped enhance the staircase's overall transparency and minimal visual impact. The so-called Hub Staircase and Daylit Gallery at the V&A were completed in December 2009 and were opened to the public in early 2010.The new Daylit gallery is a key component of the relocated and refurbished Medieval and Renaissance Galleries at the V&A, a project designed by UK architects MUMA working with restoration specialist Julian Harrap Architects. The new galleries occupy ten rooms in the south-east corner of the V&A, which had previously been isolated from the rest of the building and lacked physical and visual connections to the adjacent galleries. By removing an existing marble staircase, the architects were able to use the space between the old and new galleries to create the new Daylit gallery and, at one end of the space, a new lift and staircase, called The Hub, to connect various levels of the museum. Standing clear of existing walls, The Hub staircase was engineered by the London-based office of structural engineers Dewhurst MacFarlane with very thin landings and slender columns, and was cast on site in reinforced concrete. Combined with the cantilevered glass balustrades, with each panel consisting of two 10 mm tempered glass sheets with a 1.52 mm layer of SentryGlas interlayer, the overall effect is to reduce its visual impact and increase its transparency. The unobtrusive appearance of the glass balustrades was further enhanced by the unique fixing mechanism developed to secure the glass panels to the staircase. DuPont SentryGlas interlayer was specified by Dewhurst MacFarlane due to its recognized ability to create highly resilient laminates with extremely high post breakage performance. Working with the balustrade subcontractor TP Aspinall & Sons of Heysham (UK), the balustrades were designed and tested according to British Standards BS 6180:1999 for barriers in and about buildings and BS 6399-1:1996 for loading in buildings, amongst others. For example, two alternative designs – one produced using SentryGlas interlayer, the other using a standard PVB glass foil to laminate the glass – were tested by the Dutch company Octatube International BV to determine their ability to withstand both static and dynamic loads. "The laminated glass panels made with SentryGlas passed both of the tests, while the PVB alternative had already failed during static loading, making a subsequent dynamic load test superfluous, " recalls Simon Aspinall, director at TP Aspinall & Sons. During the pendulum test used to determine the impact resistance of the balustrade design under dynamic loads, the inside panel of the laminate made with SentryGlas was observed to break on initial impact. Yet the outside panel was undamaged and the glass panel itself remained safely in place, even after a second pendulum test, leading to a positive overall result. write your comments about the article :: © 2010 Construction News :: home page |