Low-damage novel steel plate shear walls for improved seismic performance

加拿大东部和西部城市的地震风险是众所周知的。加拿大保险局2013年进行的地震风险评估研究强调，西部和东部地区地震造成的经济损失估计可能分别高达750亿美元和610亿美元。因此，有必要开发新的结构体系，使其具有更好的延性和强度，同时在地震后仍基本不受破坏。钢板剪力墙延性大、吸能能力强，是一种有效的建筑抗震抗侧向荷载体系。然而，在设计水平的地震作用下，由于填充板的屈曲和屈服，以及边界构件的部分屈服，预计常规的SPSWs将遭受严重的破坏，从而导致地震后的大范围残余侧移。这可能会使这样一个受损的结构无法使用。在该建筑投入使用之前，需要进行昂贵的维修或拆除和重建。此外，加拿大有大量地震不足的老建筑，需要立即进行抗震改造。因此，这项研究计划的长期目标是开发低损害钢板剪力墙体系，以提高延性、强度、能量耗散能力，并减少极端事件中的永久变形，并为这些新结构体系开发设计指南和分析工具，供工程界使用。在短期内，申请人将开发两种新的低损伤SPSW系统：i)具有刚性基础的SPSW系统，其中填充板仅连接到梁；以及ii)具有摇动基础和易于更换的消能保险丝的SPSW系统，其中填充板连接到梁和柱，或仅连接到梁，并通过对新型低损伤SPSW系统进行广泛的实验测试和数值模拟来制定设计程序。建议的低损伤钢板剪力墙体系比传统的SPSWs和其他抗侧向荷载体系具有许多优点。低损伤的SC-SPSW体系具有一个新的特征，将结构恢复到原来的位置，将损伤限制在易于更换的保险丝上，并允许结构即使在地震后仍能继续使用。采用只连接梁式填充板、不设置摇摆基础的低损伤高性能钢结构体系，可以方便地对抗震能力较差的老旧钢结构房屋进行改造。因此，这里提出的替代方案有可能用于新建筑以及现有建筑的抗震修复。这项研究的意义是至高无上的，因为它确保了加拿大针对地震灾害的安全和安保措施的改善。这项研究将使加拿大离拥有更安全、更具弹性的基础设施更近一步。

Earthquake risks in the eastern and western Canadian cities are very well known. The seismic risk assessment study conducted by the Insurance Bureau of Canada in 2013 highlighted that the estimated economic losses from earthquakes could be as high as $75 and $61 billion in Western and Eastern regions, respectively. Thus, there is a need for the development of new structural systems that possess enhanced ductility and strength and at the same time remain essentially damage-free after an earthquake. Steel Plate Shear Wall (SPSW) is an effective lateral load resisting system for buildings against earthquakes since it has large ductility and high energy absorption capacity. However, under the design level earthquake, conventional SPSWs are expected to experience significant damage through buckling and yielding in infill plates and partial yielding in the boundary members leading to large residual lateral drift following an earthquake. This could render such a damaged structure unusable. Costly repairs or demolition and reconstruction will be required before the structure can be made usable. Also, Canada has a large inventory of seismically deficient old buildings that require immediate seismic retrofitting. Thus, the long-term objective of this research program is to develop low-damage steel plate shear wall systems that show improved ductility, strength, energy dissipation capacity, and reduced permanent deformations during extreme events and also develop design guidelines and analysis tools for these new structural systems to be used by the engineering community. In the short term, the applicant will develop two novel low-damage SPSW systems: i) SPSW system with a rigid base where infill plate is connected only to the beams and ii) SPSW system with rocking base and easily replaceable energy dissipating fuses where infill plate is connected to both beams and columns or only to the beams, and develop design procedure by performing extensive experimental tests and numerical simulations on the novel low-damage SPSW systems. The proposed low-damage steel plate shear wall systems offer a lot of advantages over conventional SPSWs and other lateral load resisting systems. The low-damage SC-SPSW system has a novel feature that will help the structures regain original positions, limit damage to easily replaceable fuses, and allow structures to remain in service even after an earthquake. The low-damage high-performance SPSW system with beam-only connected infill plate and without the rocking base can easily be implemented to retrofit seismically deficient old steel buildings. Thus, the alternatives presented here can potentially be used for new construction as well as for seismic rehabilitation of existing buildings. The significance of this research is paramount, as it ensures improved safety and security against seismic hazards in Canada. This research will take Canada significantly closer to having a safer and resilient infrastructure.