4Glass in architectureAlthough these windows are very dramatic they need extensive supporting masonry as they weaken the structure.
5Crystal palace, London , 185119th century greenhouse, Madrid, Spain
6Glass in architectureAlthough glass appeared to take a leading role it was still only a material that separated the interior and exterior.It was only some twenty years ago that glass started to be used in a limited structural role.
7Grand Serres of cite des sciences et de l’industrie at la Villette
8Glass in architectureThis marks a transition from non-structural to limited structural use of glass.This also raised the important question:How far can we go in usingglass as a structural material ?
9Glass as a structural material It also raises the question of what loads we can put on glass in :TensionBendingCompressionBending will be the focus of this presentation
19Stainless steel reinforcement In 1995 the ZAPPI research program started.Goals was to develop safe transparent components for a transparent building of 20×20×20 meters.This means beams of large span, column’s etc. as well as the technology to put it together.
29Further improvementAlthough the 2004 result showed large and safe beams can be made research is continuing in several directions.This with the following aims :
30Further improvement how to increase the ease of manufacture what is the required volume of reinforcementwhat is the optimum configuration for the reinforcement- what is the optimum configuration for the glassWhat is the best adhesive for the reinforcementWhat is the maximum length that can be attained
38Conclusions The results so far show that reinforced glass beams : can exceed the 6 meter length limitation imposed by the standard glass panel sizecan have a build in structural safety mechanism which shows considerable deformation after initial cracking and thus cannot collapse spontaneouslycan in theory be used as structural member of the main load bearing constructionhave a length limit of about 20 mcan result in innovative architectural solutions
39ConclusionsThe main obstacles to introduction of reinforced glass beams are:the lack of an adequate knowledge base on which to design the componentsthe problem in joining the glass components togetherthe lack of knowledge about these components at the architecture and engineering levelthe lack of clearly applicable building codes for the regulatory bodythe need for specialised staff and expertise for the contractor