Post glass breakage performance of SentryGlas® interlayer key to new glass floor and balustrades at The Eiffel Tower, Paris
Laminated safety glass with SentryGlas® ionoplast interlayer is helping to ensure the safety and security of visitors to the recently upgraded glass floor and balustrades on the first floor of The Eiffel Tower – the most visited paying monument in the world.
Architectural firm Moatti-Riviere was commissioned by SETE (the company that operates the Eiffel Tower) to transform the 5,000 square metre (54,000 square feet) first floor space into one of the most spectacular places to visit in Paris. The refurbished first floor of the Eiffel Tower, which opened in October 2014, now offers visitors a double attraction: an incredible view of the city, as well as a unique view of the Tower itself.
This was accomplished by installing clear glass guardrails around the Tower’s central opening and, behind these barriers, a path of transparent glass. At a height of 57 metres (187 feet) above the ground, visitors now have the impression of walking on air above the overhanging vantage point of the first floor – adding considerable appeal to this already popular tourist attraction.
The original opaque floor has been partly replaced by a 128 square metre (1380 square feet) glass floor. Laminated safety glass with SentryGlas® interlayer is installed in the first floor, in both the glass floor and the balustrades, which are inclined outwards.
RFR, structural engineers on the project, advised the architect on what was possible in terms of glass structures and were responsible for the design preliminary calculations for the glass floor, facades and balustrades, checking of contractors drawings and site supervision. Niccolo Baldassini, Managing Director at RFR, commented: “For such a prestigious public building project, it was critical that all safety and security regulations were met. The Eiffel Tower is a muchvisited attraction and so we had to be absolutely certain that the crowded floor spaces were designed and tested to the most stringent building safety standards. The glass floor and balustrades were tested by the national organisation in charge CSTB: ATEX No. 1968.”
“The primary reason for choosing SentryGlas® interlayer for the glass floor and balustrades was its excellent post glass breakage performance, which ensures that the glass remains in place and has a residual resistance even if all the layers are broken, providing maximum safety for visitors. We did consider using PVB as the interlayer, but this could not provide the post-breakage safety or thickness [weight] reduction advantages that SentryGlas® interlayer provides. In addition, for the glass balustrades, the transparency and open edge stability of SentryGlas® interlayer were also important factors,” he added.