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出台，Entuitive的任务是评估现有玻璃系统的脆弱性，这些系统包括加拿大市中心高层建筑的很大一部分围护系统。过去发生的事件，包括1996年英国曼彻斯特和1995年俄克拉何马城爆炸事件的证据表明，大量受伤往往是由于建筑围护结构组件(包括玻璃幕墙)受到广泛破坏而造成的，可能发生在距离引爆地点相当远的地方。为了解决这个问题，在过去的二十年里，除了用于设计和分析承受爆炸载荷的窗户的软件(例如USACE 2012)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，目前为提高建筑物玻璃幕墙的爆破性能和修复(硬化)而实施的措施差别很大。这些加固措施可能涉及单独或组合使用各种战略，包括：碎片保持膜、夹层玻璃、防爆窗帘、防爆系统(例如防爆缆索/拉杆改装和能量吸收系统)、网状网和次级窗户系统。然而，目前的北美标准(CSA S850-12和ASCE59-11)中没有关于建筑围护结构性能指标的指南，以满足

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