Seismic design and evaluation of high-rise concrete shear wall buildings in Canada

这项研究计划的长期目标是减少在加拿大高层建筑中生活和工作的人们的危害。最终将经历一次大地震的大温哥华地区，拥有比西雅图和波特兰加起来还要多的高层建筑。许多这些剪力墙建筑是在加拿大建筑规范采用现代抗震设计要求之前建造的。这项研究涉及到工程师评估现有建筑的地震安全性和设计新建筑所需的方法的发展。这项研究计划涉及许多相关的项目。这个长期研究项目的许多先前的项目都对加拿大建筑规范和HQP产生了重大的变化，这对从事这类地震评估和设计的工程公司有很高的要求。****在接下来的五年里，项目将包括：****薄混凝土墙的旧建筑的地震安全。在加拿大，这种建筑对地震的危害很大，因为它们普遍存在，占用率高，而且它们在地震中表现不佳的可能性很大。与美国的建筑不同，加拿大的许多老建筑都有薄的混凝土墙作为抗震系统和重力荷载抵抗系统。将进行两个项目-一个是使用非线性动力分析来考虑典型的非对称墙壁布置，研究建筑物的整体响应，另一个是使用非线性有限元分析来研究不连续的影响。****地震荷载作用下混凝土墙体抗剪抗力合理模型的建立。在评估现有建筑物或设计新建筑物时，工程师面临的最大挑战之一是在地震荷载下提供足够的混凝土墙抗剪力。目前的方法是从施加了许多小时的重力载荷的试验中发展出来的。新的实验室试验将在模拟剪力墙上进行，以确定混凝土墙在地震荷载下的抗剪能力。墙体将受到复杂的一阶模态位移模式和复杂的高阶模态剪力模式，这些模式由建筑物的非线性分析确定。抗剪能力将取决于如何计算需求，例如，地震期间的单次最大剪切力脉冲。****剪力墙建筑基础评价。新建筑的剪力墙通常在到达地基之前穿过许多层，而旧建筑的剪力墙通常直接在浅基座上支撑。将进行研究，以完善预测非线性基础转动和力分布在高度不确定的系统中，当剪力墙延伸通过许多低于等级的隔板

The long-term objective of this research program is to reduce the hazard for people living and working in high-rise buildings in Canada. Metro Vancouver, which will eventually experience a large earthquake, has more high-rise buildings than Seattle WA and Portland OR combined. Many of these shear wall buildings were built prior to modern seismic design requirements being adopted in Canadian building codes.***The research involves development of the methods engineers need to evaluate the seismic safety of existing buildings and design new buildings. The research program involves a number of related projects. Many previous projects from this long-term research program have resulted in significant changes to the Canadian building codes and the HQP that have been involved are in high demand by engineering companies that do this type of seismic evaluation and design.****Over the next five years, the projects will include:****Seismic safety of older existing buildings with thin concrete walls. Such buildings contribute significantly to the seismic hazard in Canada because of their prevalence, high occupancy and the likelihood that they will not perform well in an earthquake. Unlike buildings in the US, many of the older buildings in Canada have thin concrete walls as the seismic-force resisting system and the gravity-load resisting system. Two projects will be done - one looking at the global response of buildings using nonlinear dynamic analysis accounting for the typical non-symmetrical arrangement of walls, and a second looking at the influence of discontinuities using nonlinear finite element analysis.****Development of a rational model for the shear resistance of concrete walls subjected to earthquake loading. One of the greatest challenges engineers face when evaluating existing buildings or designing new buildings is providing sufficient shear resistance of concrete walls subjected to earthquake loading. The current methods were developed from tests with gravity loads applied for many hours. New laboratory tests will be conducted on simulated shear walls to determine the shear resistance of concrete walls subjected to earthquake loading. The walls will be subjected to a complex pattern of first mode displacements and a complex pattern of higher mode shear forces determined from nonlinear analyses of buildings. The shear resistance will depend on how the demand is calculated, e.g., single maximum shear force pulse during an earthquake.****Evaluation of shear wall building foundations. Shear walls in new buildings often extend through many levels below grade before reaching the foundation, while older buildings often have shear walls supported directly on shallow footings. Research will be done to refine the prediction of nonlinear foundation rotations and the force distribution in the highly indeterminate system when shear walls extend through numerous below-grade diaphragms.**