点支式中空玻璃承载性能的有限元分析

Finite Element Analysis to Point-Supported Insulating Glass Unit Bearing Properties

中空玻璃承受均布横向荷载时,外、内片与密封气体之间产生复杂的交互作用,现行规范(程)基本按抗弯刚度比例在外、内片玻璃之间分配荷载。本文使用有限元法,分析点支式中空玻璃在承受均布横向荷载时的结构特性,利用迭代计算精确地求解外荷载在外、内片间的分配比例,计算与实验测值吻合得较好。本文指出,宽厚比、中空层厚度等因素对于荷载分配比例均有较大影响,在某些情况下,直接承受荷载的外片可能承受绝大部分的荷载,规范(程)的设计方法仍值得商榷。同时,本文建议在设计中考虑中空层温度变化对承载性能的影响。

When an insulating glass unit is subjected to a uniform lateral pressure,a complex interaction occurs among the leeward,windward plates and the air trapped inside the unit.The existing code and specification distribute the loads between the two plates according to their bending stiffnesses.Finite element method is adopted to analyze the structural behaviors of the insulating unit,and an iterative procedure is developed to permit accurate analysis of load sharing between the leeward and windward plates.The following conclusions are achieved that the load sharing result is affected significantly by the aspect ratio,insulating layer thickness,etc.,and the windward plate may carry most of the lateral loads under certain conditions.It is suggeted that the design criterion method for load sharing in existing Chinese code should be modified, and the temperature variations should be taken into account in design process.