Seismic performance assessment and design tools for structural concrete elements having hybrid reinforcement

具有混合钢筋的结构混凝土构件的抗震性能评估和设计工具

• 批准号: 514368-2017
• 负责人: Alam, Shahria
• 金额: $ 2.33万
• 依托单位: University of British Columbia
• 依托单位国家: 加拿大
• 项目类别: Collaborative Research and Development Grants
• 财政年份: 2019
• 资助国家: 加拿大
• 起止时间: 2019-01-01 至 2020-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=684429
• 关键词: Seismic; performance; assessment; design; tools

Insurance Bureau of Canada estimated the overall loss after a 9.0-magnitude earthquake in British Columbia at almost $75B, which reflects the vulnerability of Canadian civil infrastructure. Harsh winter is another critical factor for deterioration of Canadian infrastructure where de-icing salt causes accelerated corrosion to steel. Fibre-reinforced polymer (FRP) bars were introduced as reinforcement in concrete structures to prevent corrosion. However, FRP is a brittle material without inelastic branch. Thus, FRP reinforced concrete (RC) structures exhibit poor ductility with low energy dissipation capacity leading to a major problem in seismic design. This issue can be addressed by introducing hybrid reinforcement where FRP bars can be used along with a ductile material, e.g. steel, or shape memory alloy (SMA) rebar to introduce ductility. FRP rebar cage can be placed in the exterior cage to provide corrosion resistance whereas steel can be used in the inner cage to provide ductility. Since SMA is also good against corrosion but costly, it can be placed at the plastic hinge region, and spliced with other rebar type in the outer cage of RC elements. Little research has been directed towards hybrid reinforcement where FRP rebar is used along with another ductile material and using spliced connections. This study will determine the seismic behavior of concrete bridge piers having hybrid reinforcement, and compare its performance to that of a regular steel RC bridge piers in terms of load-displacement, moment-rotation and energy dissipation capacity, and strains in the longitudinal and transverse reinforcements. Currently, there is no numerical tool available to predict the response of RC elements having hybrid reinforcements. Hence, another important objective of this study is to develop numerical tools to predict the response of RC elements having hybrid reinforcements in terms of moment-curvature response, pushover response, and seismic response and implement them in S-Frame Software. These tools will assist in developing performance-based design guidelines and performing fragility assessment for such hybrid RC elements and structures.

加拿大保险局估计，不列颠哥伦比亚省9.0级地震后，总体损失近75B加元，这反映了加拿大民用基础设施的脆弱性。冬季恶劣是加拿大基础设施恶化的另一个关键因素，去冰盐会导致钢加速腐蚀。在混凝土结构中引入了纤维增强聚合物（FRP）棒，以防止腐蚀。但是，FRP是没有非弹性分支的脆性材料。因此，FRP钢筋混凝土（RC）结构表现出较差的延展性，而能量耗散的能力低，导致地震设计的主要问题。可以通过引入混合加固，可以解决此问题，在该材料中可以将FRP棒与延性材料一起使用，例如钢或形状记忆合金（SMA）钢筋引入延展性。可以将FRP钢筋笼子放在外部笼子中以提供耐腐蚀性，而钢可以在内部笼子中使用以提供延展性。由于SMA也适合腐蚀，但昂贵，因此可以将其放置在塑料铰链区域，并在RC元件的外笼中与其他钢筋类型剪接。几乎没有针对混合增强的研究，其中使用FRP钢筋与另一种延性材料以及使用拼接连接一起使用。这项研究将确定具有混合增强材料的混凝土桥墩的地震行为，并将其与常规的钢RC桥墩的性能进行比较，从负载解散，力矩移动和能量耗散能力以及纵向和横向增强剂中的菌株进行了比较。当前，尚无数值工具来预测具有混合增强件的RC元素的响应。因此，这项研究的另一个重要目标是开发数值工具，以预测具有混合增强件的RC元素的响应，从矩侵性的响应，俯卧撑响应和地震响应方面，并在S型框架软件中实现它们。这些工具将有助于制定基于绩效的设计指南，并对此类混合RC元素和结构进行脆弱性评估。