玻璃幕墙结构力学性能试验分析与数值模拟

Experimental analysis and numerical simulation of mechanical behavior of glass curtain walls

结合工程实例对玻璃幕墙结构进行了风压变形性能试验研究,建立了风荷载作用下幕墙结构的整体有限元模型,并进行了数值模拟计算。通过对试验与有限元模拟结果的分析比较可以看出,该整体有限元模型主要受力杆件面法线方向最大挠度值的数值模拟结果与实验基本吻合,并在规范规定的容许值范围内。但试验结果在立柱下端节点处呈现明显的非线性变化,数值模拟结果与试验结果差别较大。本文根据弯矩—曲率(M—θ)关系,采用弹性杆来模拟立柱两端梁柱节点处的半刚性状态。数值结果表明,这种半刚性模型比较符合实际情况,计算值与试验值吻合较好,为幕墙结构力学分析提供了一种新的建模方法。

To analyze the mechanical behavior of glass curtain walls, an experimental study on the deformation of a glass curtain wall under wind pressure was carried out for an actual engineering project. An integral finite element （FE） model of the curtain wall under wind load was created for the numerical simulation. Comparing the experimental results with those by the numerical simulation, it was noted that the maximum normal deflection of the vertical mullion of the glass curtain wall by the FE model quite agrees with the experimental results and they are all within the specifications of the standard criteria. But the experimental results of the deflections near the lower end of the vertical mullion have obvious nonlinear relationship with the pressures and are quite different from those obtained by the numerical simulation. Based on the moment-curvature （M-θ） relationship, elastic bar elements were adopted to model the half-rigid status of the frame nodes at the two ends of the mullions, which was a new modeling approach for the mechanical analysis of curtain walls. It is found that the half-rigid model is a good representation of the real node cases. Numerical results by the half-rigid model agree with those obtained by the experiment.