Seismic Design and Evaluation of Concrete Bridges and Buildings

该研究计划涉及两个主要领域，包括两个关于地震工程的项目和两个关于混凝土基础设施性能的项目。**将对桥梁的抗震性能进行研究，以评估2014年加拿大公路桥设计规范中新制定的抗震设计条款。将开发预测不同级别地震引起的桥柱损坏程度的方法，以帮助桥梁设计者执行新的基于性能的设计程序。其目标是提供一种设计方法，不仅要防止坍塌，而且要将较小、更频繁的地震事件的损害降至最低。将进行反复荷载试验，研究如何预测有缺陷的既有桥梁结构的损伤指标，并开发预测可能损伤程度的分析工具。这项发现赠款旨在提高在适当的地震设计程序可用之前设计的旧桥的安全性，并将对不同级别地震的可能损害进行评估。这项研究将提高对新桥和既有桥梁地震反应预测的知识水平，并将导致加拿大公路桥梁设计规范中抗震设计条款的改进。**研究基础旋转对建筑物地震反应的影响，以了解发生的复杂的土壤-结构相互作用。本研究计划的目的是考虑剪力墙底部基础的旋转增加剪力墙灵活性的影响。借助于非线性有限元分析和足尺梁柱板子组件的反复加载试验，将制定低延性框架构件节点所需的配筋细节和抗剪钢筋，以评估CSA标准A23.3对混凝土结构设计的合适要求。这些类型的框架在加拿大东部和中部很常见，但关于这些框架构件的细节效果的信息很少。这两个研究项目将促进对基础转动的影响以及中低延性框架的地震反应的理解。这项研究将导致对CSA混凝土结构设计标准的改进。**将为高层建筑开发使用超高强度混凝土时实现延性柱的设计和细节要求。在保护层突然剥落后，约束加固必须有效，以提供延性响应。还将研究使用钢纤维自固结混凝土作为部分替代延性柱中的约束钢筋的方法。这将产生一种可行的混凝土混合料，并增加纤维的好处，并有可能减少延性柱的拥堵。这项研究将促进对这些新型混凝土性能的了解，并将为柱的约束提供实用的解决方案。**将调查在厚板混凝土桥梁中使用钻孔锚杆提供抗剪钢筋以避免剪切破坏，并将调查碱-硅酸反应对剪切强度的影响。研究防止停车场结构受钢筋锈蚀和剥离影响的连续倒塌的方法。这两项研究的目的是防止现有破旧的桥梁和停车场结构出现故障。

The research program involves two main areas with two projects on earthquake engineering and two projects on the performance of concrete infrastructure.**Research will be carried out on the seismic performance of bridges to assess the newly developed seismic design provisions of the 2014 Canadian Highway Bridge Design Code. Methods for predicting damage levels in bridge columns due to different levels of earthquakes will be developed to assist bridge designers in carrying out the new performance-based design procedures. The goal is to provide a design approach that is not only concerned about preventing collapse but also minimizing damage for smaller, more frequent seismic events. Reversed cyclic loading experiments will be carried out to study ways of predicting damage indicators for deficient existing bridge structures and analytical tools for predicting the extent of possible damage will be developed. This Discovery Grant is aimed at improving the safety of older bridges that were designed before proper seismic design procedures were available and will also provide an assessment of likely damage for different levels of earthquakes. This research will advance the state of knowledge in predicting the seismic response of new as well as existing bridges and will lead to improvements of the seismic design provisions of the Canadian Highway Bridge Design Code. **Studies on the effects of foundation rotation on the seismic response of buildings will be carried out to gain an understanding of the complex soil-structure interaction that takes place. The aim of this research program is to account for the effects of the increased flexibility of shear walls due to the rotations of the foundations at the base of the walls. With the aid of non-linear finite element analysis and reversed cyclic loading tests of full-scale beam-column-slab sub-assemblies, the reinforcement details and shear reinforcement required in joints of lower ductility frame members will be developed to assess suitable requirements for the CSA Standard A23.3 on the Design of Concrete Structures. These types of frames are common in eastern and central Canada and yet there is little information on the effects of the detailing of these frame members. These two research projects will advance the understanding of the effects of foundation rotation and the seismic response of frames of moderate and low ductility. This research will result in improvements to the CSA Standard for the Design of Concrete Structures.**Design and detailing requirements for achieving ductile columns when using ultra-high-strength concrete will be developed for use in high-rise construction. The confinement reinforcement must be effective to provide a ductile response after sudden cover spalling occurs. The use of self-consolidating concrete with steel fibres will also be investigated as a means of partial replacement of confinement reinforcement in ductile columns. This would result in a workable concrete mix with the added benefit of the fibres and has the possibility of reducing the congestion in ductile columns. This research will advance the state of knowledge on the performance of these new types of concrete and will provide practical solutions for the confinement of columns.**The use of drilled-in anchors used to provide shear reinforcement in thick slab concrete bridges to avoid shear failures will be investigated and the effects of deterioration due to alkali-silica reactivity on the shear strength will be investigated. Ways of preventing progressive collapse in parking garage structures affected by corrosion of the reinforcement and delamination will be studied. These two studies are aimed at preventing failures in existing deteriorated bridge and parking garage structures.