爆炸作用下点支式玻璃幕墙的破损机制和模式研究

Point-supported glazing has been widely adopted in large scale public buildings. Because high speed flying glass shards is the main cause of blast-induced casualties, it is very important to evaluate the blast-resistance of glazing. To mitigate the blast consequence, this project proposes to develop an analysis and evaluation method for the blast-resistance of point-supported glazing...Based on the static tensile and compressive tests, the static mechanical property of glass in tension and in compression can be obtained. The strain rate effect on glass's mechanical property then be studied through impact tests employing the intermediate strain rate material property test facility and the dynamic material property model will be set up. The static tensile and shear property of PVB (Polyvinyl butyral), the interlayer of laminated glass, can be obtained through the static tests. The mechanical property of PVB at high strain rate can be studied based on the impact tests and the dynamic material property model is then set up. Considering the real performance of PVB, a finite element model of laminated glass is to be established and its effectiveness will be verified by comparing the measured response from the heap load test on simple-supported laminated glazing panel with that from numerical study based on the proposed model. Taking into account the effects of such details as panel holes, metal fasteners and cushion rubber, a high fidelity finite element model will be built. The model will then be employed to investigate the nonlinear dynamic response of point-supported glazing subjected to blast loading. Considering the influence of scale distance, dimension of glazing panel, composition of laminated glass and supporting stiffness on the blast-resistance, the damage mechanism and damage mode will be revealed and verified though the field blast test. Finally a series of practical P-I diagrams for different damage modes will be produced from parameteric analysis...The research results from this project can be applied for the blast-resistance design and/or evaluation of point-supported glazing.

点支式玻璃幕墙在公共建筑中广泛应用，而爆炸引起的高速飞行的玻璃碎片是爆炸造成人员伤亡的主要因素。为减少爆炸产生的后果，本项目提出研究爆炸冲击波作用下点支式玻璃幕墙的破损机制和模式。.首先通过静力拉伸和压缩试验，确定玻璃的静态拉、压力学模型；通过中应变率冲击试验，研究应变率效应对玻璃力学性能的影响并建立理论模型；通过静力拉伸和剪切试验，确定PVB的静态拉、剪力学模型，并通过试验研究PVB的松弛特性；通过冲击试验，研究应变率对PVB力学性能的影响，并建立理论模型；然后考虑PVB的实际抗剪刚度，建立夹胶玻璃的力学模型，并通过堆载试验进行验证；建立细致的有限元模型，分析点支式玻璃幕墙在爆炸冲击波作用下的动态反应过程、破损机制和破损模式，并通过现场爆炸试验进行验证；最后通过系统的参数分析，建立评估点支式玻璃幕墙抗爆性能的系列P-I图。.本项目的研究成果可用于点支式玻璃幕墙的抗爆设计和抗爆性能评估。

本项目主要对浮法玻璃及PVB夹胶材料的静动态力学性能，以及爆炸冲击波作用下单片玻璃幕墙、点支式夹层玻璃幕墙的破损机制进行了系统性研究，主要取得以下成果：.1) 通过浮法玻璃的准静态力学性能试验，确定了其轴拉、弯曲及轴压强度等力学指标。基于Monte Carlo模拟方法阐释了强度数据离散现象以及尺寸效应，建立了玻璃面板强度随尺寸的变化关系；.2) 通过系列动态压缩试验和动态劈裂试验，研究了浮法玻璃动态压缩强度及动态劈裂强度与应变率的关系，其中压缩强度具有一定的应变率效应（10-3s-1~800s-1），而劈裂强度的应变率效应（10-3s-1~40s-1）较明显；建立了浮法玻璃的动态本构模型；.3) 通过系列单轴拉伸试验、剪切试验和松弛试验，研究了温度（-30℃～40℃）和应变率（10-3s-1～200s-1）对PVB力学性能的影响： PVB材料具有明显的应变率及温度相关性，抗拉强度与剪切模量随温度升高而降低，随应变率升高而升高；建立了PVB材料的应变率及温度相关本构关系；.4) 建立了点支式玻璃幕墙抗爆性能分析的力学模型，并通过现场爆炸试验进行验证；结合参数分析，研究了几何尺寸对位移响应和破坏模式的影响；建立了可用于夹层玻璃抗爆性能评估的P-I曲线；.5) 通过理论分析及现场爆炸试验研究了单层玻璃板的受爆破碎机理，基于能量原理提出了玻璃碎片尺寸及飞溅距离的评估方法。.项目成果可用于夹层玻璃幕墙抗爆设计和抗爆性能评估。