At Gravesend Glass, we have followed the ongoing production methods of Glass. The most important testing is done by the ASTM E1300 Task Group, which has expanded the glass standard in response to the needs of users and fitters like us here at Gravesend Glass.
However, while this standard still only applies to an all glass types of rectangular shape, all assumptions have changed to show the standard’s expanded nature. The standard now closely addresses two, three and four-sided supports where the edges are simply supported and free to slip straight into the plane. Glass edge support on just two sides is assumed to behave just like a simply supported beam and also glass supported on just one side is assumed to behave normally. The charts have been extended to show all aspect ratios up to ten.
From the original charts, the glass standard now has more than eighty. Where the standard first concentrated only on rectangular shapes of monolithic glass that were supported on all four sides, it now includes normal charts for three, two and one-sided glass supporting conditions. In addition, a companion glass deflection chart that enables the glaziers to determine the approximate lateral deflection accompanies each non-factored glass load chart. The factors for all glass laminates also have been taken away, and a new series of non-factored loads as well as deflection charts for glass laminates has been added on to them.
As more research has been intensely conducted on the strength of laminated glass, this task group has been able to include this information into the standard. Insulating glass can be separated into several types— these units with monolithic glass lights of equal (symmetric) types and thicknesses, simply supported continuously along all four sides. Those with one or two monolithic lites and one laminated lite under short or longer duration loads; and those that have laminated glass over laminated glass, like we often do at Gravesend Glass, not just under short but long duration loads.