Design and Evaluation of Critical Concrete Elements

其目标是改善对桥梁和建筑结构性能起主要作用的关键混凝土构件的响应。这涉及实验和分析研究，以预测新元件以及现有缺陷结构元件的行为。总体目标是改善加拿大基础设施的性能。将对桥梁的抗震性能进行研究，以评估最近制定的2014年加拿大公路桥梁设计规范的抗震设计规定。将对圆形和矩形柱进行反向循环荷载试验，以评估其在潜在塑性铰区域的抗剪性。其目的是为典型桥梁柱的抗剪强度制定更合理的设计规定。这项实验研究还将评估在2019年拟议的代码修改中调整的损坏指标。这些损伤指标是评估桥梁性能的关键。将开发现有桥梁结构中缺陷柱的响应和用于预测可能损坏程度的分析工具。其目标是提高新桥梁和旧桥梁的安全性，这些桥梁是在适当的抗震设计和详细设计程序可用之前设计的。 将研究有缺陷的旧桥的评估和改造。有许多有缺陷的桥梁，其加固细节较差，许多桥梁还遭受混凝土劣化和钢筋腐蚀的影响。将对细节有缺陷的构件（如裂缝控制钢筋数量不足和横向钢筋锚固细节不良）进行一系列试验。将对用于在厚板混凝土桥梁中提供抗剪钢筋的钻孔锚的使用进行进一步的调查，以避免剪切破坏和由于碱-硅反应对剪切强度的劣化的影响。将进行进一步的实验和分析研究，以研究防止连续倒塌的方法。可能的冲剪破坏在停车库结构的钢筋腐蚀和分层的影响将进一步研究。平板结构的非线性分析将检查初始冲切破坏发展为连续倒塌的可能性，如果满足结构完整性加固应用的规范要求。 设计和详细要求实现延性柱时，使用超高强度混凝土将开发用于高层建筑。约束钢筋必须有效地提供一个延性反应后，突然盖剥落发生。将研究在柱中使用纤维增强高强度混凝土，通过在激波管测试设施中测试柱来确定其抗爆性。

The goal is to improve the responses of critical concrete elements that play a major role in the performance of bridge and building structures. This involves experimental and analytical research to predict the behavior of new elements as well as existing deficient structural elements. The overall objective is to improve the performance of Canada's infrastructure. Research will be carried out on the seismic performance of bridges to assess the recently developed seismic design provisions of the 2014 Canadian Highway Bridge Design Code. Reversed cyclic loading tests will be carried out on circular and rectangular columns to assess their shear resistance in regions of potential plastic hinges. The objective is to develop more rational design provisions for the shear resistance of typical bridge columns. This experimental study will also enable an assessment of the damage indicators that were adjusted in the 2019 proposed changes to the code. These damage indicators are key in assessing the performance of bridges. The response of deficient columns in existing bridge structures and analytical tools for predicting the extent of possible damage will be developed. The goal is to improve the safety of new bridges and older bridges that were designed before proper seismic design and detailing procedures were available. The evaluation and retrofit of deficient older bridges will be studied. There are many deficient bridges with poor reinforcing details and many are also suffering from concrete deterioration and from corrosion of reinforcing steel. Series of experiments will be carried out on elements with deficient details such as insufficient amount of crack control reinforcement and poor anchorage details of transverse reinforcement. Further investigations will be carried out on the use of drilled-in anchors used to provide shear reinforcement in thick slab concrete bridges to avoid shear failures and the effects of deterioration due to alkali-silica reactivity on the shear strength. Further experimental and analytical investigations will be carried out to study ways of preventing progressive collapse. Possible punching shear failures in parking garage structures affected by corrosion of the reinforcement and delamination will be studied further. Non-linear analyses of flat plate structures will examine the likelihood that an initial punching shear failure will progress into a progressive collapse if the code requirements for the application of structural integrity reinforcement are satisfied. 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 fibre-reinforced high strength concrete in columns will be investigated to determine their blast resistance by testing the columns in a shock-tube testing facility.