Seismic and Blast Retrofit of Reinforced Concrete and Masonry Buildings

在最近的地震中，物理基础设施的表现清楚地表明，现有建筑库存的很大一部分很容易受到地震的影响。在20世纪70年代颁布现代抗震设计准则之前设计的建筑物，以及最近建造的那些没有适当的抗震设计和细节实践的建筑物，构成了特别高的地震风险。用新的和改进的结构取代这些有缺陷的建筑物在经济上是不可行和不实际的。因此，抗震改造（恢复和加强）仍然是土木工程基础设施有效和可行的减轻地震风险战略。除了地震风险之外，关键的基础设施也容易受到意外或恶意故意爆炸的影响。防爆设计在加拿大并不常见。加拿大国家建筑规范没有明确要求建筑的防爆设计。因此，现有的建筑物和其他实物资产很容易受到爆炸威胁，特别是如果装药重量很高（如汽车和卡车炸弹），爆炸距离建筑物很近（对峙距离）。

The performance of physical infrastructure during recent earthquakes has clearly demonstrated that a large segment of existing building inventory is vulnerable to seismic excitations. Buildings designed prior to the enactment of modern seismic design guidelines of 1970's, as well as those built more recently without the appropriate seismic design and detailing practices pose particularly high seismic risk. It is economically not feasible and practical to replace these deficient buildings with new and improved structures. Therefore, seismic retrofitting (rehabilitation and strengthening) remains to be an effective and viable seismic risk mitigation strategy for civil engineering infrastructure. In addition to the seismic risk, critical infrastructure is vulnerable against accidental or maliciously intended deliberate explosions. Blast-resistant design is not common in Canada. The National Building Code of Canada does not require explicit blast-resistant design of buildings. Therefore, existing buildings and other physical assets are vulnerable to blast threats, especially if the charge weight is high (as in the case of car and truck bombs) and the proximity of explosions to buildings (standoff distance) is close. The objective of the proposed research program is to develop new and innovative seismic and blast retrofit methodologies for structurally deficient concrete and masonry buildings. The emphasis is placed on the development of cost effective and structurally sound retrofit techniques. The proposed research will be conducted by following two phases; Phase I research will consist of the development of seismic retrofit strategies. Innovative bracing systems will be developed for non-ductile reinforced concrete frames, either in the form of diagonal prestressing or buckling restrained braces. Surface bonded fibre reinforced polymer (FRP) systems with ductile steel sheet anchors will be developed for non-ductile concrete shear walls and unreinforced masonry walls (load bearing and non-load bearing). Phase II will include development of blast retrofit methodologies for tilt-up construction and unreinforced masonry walls. The use of polyurea with or without welded reinforcement fabric will be considered for the latter application. Combined experimental and analytical research will be conducted. Large scale frames and walls will be tested under simulated seismic loading at the Structures Laboratory, and large-scale concrete and masonry walls will be tested under simulated blast loads at the Blast Research Laboratory of the University of Ottawa. The experimental research will be complemented by dynamic inelastic analysis of buildings and building components. Fragility curves for seismic risk mitigation, and pressure-impulse curves for blast performance assessment will be generated.