点支式钢化玻璃火灾下受力性能试验研究

为研究单层索网点支式玻璃幕墙中点支式单片、中空和夹胶钢化玻璃在火灾下的破裂过程，分别对点支式单片、中空和夹胶等3组开孔钢化玻璃进行了相同火灾条件下的负载试验研究。重点考察试验过程中玻璃位移随温度的发展情况、玻璃的破坏模式和破坏时间，以及其破裂过程等。通过将试验数据与相同类型的不开孔玻璃进行对比，研究了角部开孔对钢化玻璃在火灾下受力性能和破裂过程的影响。结果表明：火灾下，玻璃由于受热膨胀不均匀在表面产生的拉应力是其破坏的主要原因；玻璃面板承受的均布荷载将在玻璃内部产生荷载应力，并导致其面外变形增大；玻璃开孔，使其在四角点孔洞边缘形成大量微裂纹，造成玻璃面板孔边材料强度下降和应力集中，加剧了玻璃的破坏；点支式玻璃面板的固定支座约束限制了四边变形，加快了其中心点位移的增长。

Experimental research on mechanical performance of point supported tempered glass under fire condition

In order to research the mechanical performance of single, mid-hollow and laminated point supported tempered glasses used in monolayer cable net point-supported glass walls under fire condition, load tests were conducted on three groups tempered glass with holes under the same fire conditions. The development of displacement with temperature, failure modes, failure time, and mechanical performance of point supported tempered glass under fire condition were mainly investigated. By comparing the test data of specimens with and without openings, the impact of marginal holes on the mechanical property and mechanical performance of tempered glass under fire condition was studied. The results indicate that the tensile stress caused by uneven heating expansion on the surface is the main reason of the failure of glass. The uniform load sustained by glass panel would produce stress inside the glass, which results in the increase of out-of-plane deformation of glass. Lots of micro-cracks produced by holes lead to strength degradation and stress concentration of glass panel around the holes, thus expediting the destruction of point supported tempered glass. The deformation of four edges of point supported tempered glass is restrained by its fixed support, resulting in the acceleration of the increasing rate of central displacement.