Application of Strain Hardening Cementitious Materials in Seismic Design and Retrofit of Structures

应变硬化胶凝材料在结构抗震设计与改造中的应用

• 批准号: RGPIN-2022-05454
• 负责人: Pantazopoulou, Stavroula
• 金额: $ 2.26万
• 依托单位: York University
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2022
• 资助国家: 加拿大
• 起止时间: 2022-01-01 至 2023-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=758070
• 关键词: Application; Strain; Hardening; Cementitious; Materials

A route to reduce the environmental impact of concrete is to aim for materials that are durable, resilient, and strong with reduced energy impact and demand on natural resources; and to aim for structures that have a long service life while providing their users with safety against extreme events such as earthquakes. The advent of the development of Strain Hardening Cementitious Composites (SHCC) opens up an opportunity to address several of these concerns by taking advantage of the unique properties of this strain-resilient class of concrete materials that combine high strength with excellent crack control and significantly improved durability over common concrete. SHCCs have not yet been integrated in structural design, except for the critical regions of a few bridges with severe environmental exposure. Their widespread use has been delayed due to cost and lack of general design specifications. Thus, the full potential of SHCC is yet to be realized both in new construction and in retrofits. The strain-ductility in tension and the large range of available compressive and tensile strengths makes SHCC ideal for seismic design and rehabilitation of Structures. The proposed work will focus on formulation of a Performance-Based Design Framework for seismic resistant SHCC Structures and for seismic retrofit solutions using SHCCs. Material characterization under cyclic tension/compression, pertinent test setups, component and subassembly tests of structural systems that are either designed or retrofitted with SHCC under cyclic displacement reversals representing earthquake effects will be conducted. Hysteretic constitutive laws for advanced nonlinear simulation of structures made or retrofitted with SHCC will be formulated. The objective is to develop design models for dimensioning and detailing seismic resistant structures and retrofit schemes comprising SHCCs while exploiting the deformability of the material to reduce reinforcement detailing without compromise in performance. Results will feed into a mounting effort for the establishment of a design code for seismic design and upgrading of new and old reinforced concrete structures using SHCCs, to enable practical implementation of this technology for high performing structures and structural retrofits. The study will serve as the testbed for pre-normative evaluation of the seismic design provisions, thus benefiting the Canadian Construction Industry (material producers, precast industry and designers all benefit from new structural systems to achieve seismic resilience). Sustainability effected by prolonged service life and reduced maintenance requirements of structures is an added benefit to Canadian Society at large. The research program will provide exceptional opportunities to HQPs to become versed to novel technologies that will help them stand out in industry and academia, while also addressing many UN-SDGs; EDI is a driving consideration for planning the proposed training environment.

减少混凝土对环境影响的一种途径是寻求耐用、有弹性和坚固的材料，减少对自然资源的能源影响和需求;并寻求具有较长使用寿命的结构，同时为其用户提供抵御极端事件（如地震）的安全性。应变硬化水泥基复合材料（SHCC）的发展的到来开辟了一个机会，以解决这些问题，利用这种应变弹性类混凝土材料的独特性能，联合收割机高强度与优良的裂缝控制和显着改善的耐久性比普通混凝土。SHCC还没有被整合到结构设计中，除了一些桥梁的关键区域与严重的环境暴露。由于成本和缺乏一般设计规格，它们的广泛使用被推迟。因此，SHCC的全部潜力尚未在新建筑和改造中实现。 SHCC的拉伸应变延性和大范围的抗压和抗拉强度使其成为结构抗震设计和修复的理想材料。建议的工作将集中在制定一个基于性能的设计框架，抗震SHCC结构和抗震改造解决方案，使用SHCC。将进行循环拉伸/压缩下的材料表征、相关试验装置、结构系统的组件和子组件试验，这些结构系统在代表地震效应的循环位移反向下采用SHCC设计或改造。滞后本构关系的先进的非线性模拟与SHCC或改造的结构将制定。我们的目标是开发设计模型的尺寸和详细的抗震结构和改造方案，包括SHCC，同时利用材料的变形能力，以减少钢筋的详细性能不妥协。结果将投入到一个安装的努力，建立一个设计规范的抗震设计和升级的新的和旧的钢筋混凝土结构使用SHCC，使实际实施这项技术的高性能结构和结构改造。该研究将作为抗震设计规定的预规范评估的试验平台，从而使加拿大建筑业受益（材料生产商，预制行业和设计师都受益于新的结构系统，以实现抗震能力）。由于结构的使用寿命延长和维修要求减少而产生的可持续性对整个加拿大社会来说是一个额外的好处。该研究计划将为HQP提供卓越的机会，使他们能够精通新技术，帮助他们在行业和学术界脱颖而出，同时解决许多联合国可持续发展目标; EDI是规划拟议培训环境的主要考虑因素。