Development of a threat-oriented, risk-based analysis & design approach for blast protection of window glazing building envelope systems in downtown centres

随着新的加拿大标准CSA S850-12 -爆炸荷载下建筑物的设计和评估的引入，Entuitive的任务是评估现有玻璃系统的脆弱性，这包括加拿大市中心高层建筑的大部分建筑围护结构系统。过去事件的证据，包括1996年英国曼彻斯特和1995年俄克拉荷马城的爆炸事件，表明大量的伤害往往是由于建筑围护结构的广泛破坏，包括玻璃外墙，这可能发生在距离爆炸地点相当远的地方。为了解决这个问题，在过去的二十年中，除了用于设计和分析受爆炸载荷的窗户玻璃的软件（例如USACE 2012）之外，还提出了许多建筑物防爆标准（例如CSA S850-12和ASCE 59-11）和安全标准（例如ISC 2001）。然而，目前实施的增强防爆性能和修复（加固）建筑物玻璃立面的措施差别很大。这些加固措施可能涉及单独或组合使用各种策略，包括：碎片保留膜、夹层玻璃、防爆窗帘、捕获系统（例如捕获电缆/杆改造和能量吸收系统）、网状筛网和次级窗口系统。然而，在目前的北美标准（CSA S850-12和ASCE 59-11）中，没有关于建筑围护结构性能指标的指导方针

With the introduction of the new Canadian Standards CSA S850-12 - Design And Assessment of Buildings Subjected to Blast Loads, Entuitive is tasked with evaluating the vulnerability of existing glazing systems, which comprise a large portion of the building envelope systems within high rise buildings in downtown centers in Canada. Evidence from past incidents, including the bombings of Manchester UK in 1996 and Oklahoma City in 1995, shows that a large number of injuries often results from extensive damage to building envelope components including glass facades, which may occur at considerable distance from the detonation site. To address this problem, a number of standards for the blast protection of buildings (e.g. CSA S850-12 and ASCE 59-11) and safety criteria (e.g. ISC 2001) were put forth in the past two decades, in addition to software for the design and analysis of window glazing subjected to blast loads (e.g. USACE 2012). However, currently implemented measures for blast performance enhancement and rehabilitation (hardening) of buildings' glazing facades vary considerably. These hardening measures may involve the use of a wide range of strategies individually or in combinations, including: fragment retention films, laminated glass, blast curtains, catching systems (e.g. catch cable/bar retrofit and energy-absorbing systems), mesh screens, and secondary window systems. However, no guidelines are made available in the current North American standards (CSA S850-12 and ASCE 59-11) regarding the building envelope performance indicator necessary to