NEESR: Seismic Performance and Design of Partially-Grouted Reinforced Masonry Buildings

NEESR：部分灌浆钢筋砌体建筑的抗震性能和设计

• 批准号: 1208208
• 负责人: P. Benson Shing
• 金额: $ 115万
• 依托单位: University of California-San Diego
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-06-01 至 2016-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1208208&HistoricalAwards=false
• 关键词: NEESR; Seismic; Performance; Design; Partially

Reinforced masonry construction constitutes about ten percent of all low-rise buildings in the United States. Many of them are commercial, industrial, and school buildings. It is also used for multi-story hotels, college dormitories, and apartments. While most of the reinforced masonry structures constructed in the west coast are fully grouted, almost all reinforced masonry construction in the rest of the country, including regions of high seismic risk, has partial grouting to make it economically competitive. Walls are the main seismic load resisting elements in a masonry structure. The seismic performance of partially grouted reinforced masonry wall systems has not been sufficiently studied and is not well understood due to the complexity of their behavior, which can be attributed to the heterogeneity and anisotropy introduced by masonry blocks, block cavities, mortar joints, and grouted cells. Recent studies have shown that current seismic design provisions for partially-grouted masonry walls are not adequate and likely to be unconservative. However, the seismic safety of these structures also depends on their system-level performance, which is even less understood. This research will advance understanding of the behavior of partially-grouted masonry structures at the system, as well as component, level and develop and validate economically competitive design details and retrofit methods to make new and existing partially-grouted reinforced masonry structures better achieve current seismic performance standards. To this end, seventeen partially-grouted reinforced masonry wall components and subassemblies will be tested with quasi-static cyclic loading, and two full-scale, one-story buildings will be tested with earthquake ground motions on a shake table. An analytical method will be derived to provide more comprehensive assessment of the shear capacities of these walls than available in current codes. Furthermore, advanced computational models will be developed and calibrated with the test data to provide a simulation tool that can be used to better understand the performance of these structures at the global and local levels, and for use in performance-based seismic design. This research is a collaborative effort among the University of California at San Diego, Drexel University, and University of Minnesota. The experimental work will use the George E. Brown, Jr. Network for Earthquake Engineering Simulation (NEES) shake table at the University of California at San Diego, and the hybrid simulation facility at Lehigh University. Data from this project will be archived and made available to the public through the NEES Project Warehouse/data repository (http://www.nees.org).Reinforced masonry has many desirable properties as a construction material, such as durability and energy efficiency. Masonry can also contribute significantly to green and sustainable construction with the use of recycled aggregate and high quantity of fly ash in the ingredients. However, the lack of adequate research and well-developed seismic design provisions as compared to other construction materials has led to a steady decline in the use of reinforced masonry. The seismic performance of partially-grouted masonry is of primary importance for many regions in the United States that are susceptible to low-probability but high-consequence seismic events. The research will result in economically competitive design details and retrofit methods to enhance the seismic performance and safety of these structures. The research will provide unique educational experiences and training to graduate and undergraduate students at the three participating universities. The K-12 education component will develop a demonstration module that relates mathematics and sciences to technologies that enhance the safety of the built environment. The project will utilize an advisory panel with members from code development bodies, industry, and professional practice. Research results and recommendations from this project will be communicated to relevant seismic design code committees for timely implementation to lead to safer, earthquake-resilient masonry construction. This award is part of the National Earthquake Hazards Reduction Program (NEHRP).

钢筋砌体建筑约占美国所有低层建筑的百分之十。其中许多是商业、工业和学校建筑。也用于多层酒店、大学宿舍、公寓等。虽然西海岸建造的大多数钢筋砌体结构都进行了完全灌浆，但该国其他地区（包括地震高发地区）几乎所有钢筋砌体结构都进行了部分灌浆，以使其具有经济竞争力。墙体是砌体结构中主要的抗震荷载构件。部分灌浆钢筋砌体墙系统的抗震性能尚未得到充分研究，也由于其行为的复杂性而未被充分理解，这可归因于砌块、砌块空腔、砂浆接缝和灌浆引入的不均匀性和各向异性细胞。最近的研究表明，目前针对部分灌浆砌体墙的抗震设计规定不够充分，而且可能不够保守。然而，这些结构的抗震安全性还取决于它们的系统级性能，而这一点却鲜为人知。这项研究将加深对系统中部分灌浆砌体结构的性能以及组件、水平的理解，并开发和验证具有经济竞争力的设计细节和改造方法，以使新的和现有的部分灌浆钢筋砌体结构更好地达到当前的抗震性能绩效标准。为此，十七个部分灌浆的钢筋砌体墙构件和组件将进行准静态循环荷载测试，两座全尺寸的单层建筑将在振动台上进行地震地面运动测试。将导出一种分析方法，以提供比现行规范中可用的更全面的墙体抗剪能力评估。此外，将开发先进的计算模型并利用测试数据进行校准，以提供模拟工具，可用于更好地了解这些结构在全球和局部层面的性能，并用于基于性能的抗震设计。这项研究是加州大学圣地亚哥分校、德雷克塞尔大学和明尼苏达大学之间的合作成果。实验工作将使用加州大学圣地亚哥分校的 George E. Brown, Jr. 地震工程模拟网络 (NEES) 振动台和里哈伊大学的混合模拟设施。该项目的数据将被存档并通过 NEES 项目仓库/数据存储库 (http://www.nees.org) 向公众开放。作为建筑材料，钢筋砌体具有许多理想的特性，例如耐久性和能源效率。通过在成分中使用再生骨料和大量粉煤灰，砌体还可以为绿色和可持续建筑做出重大贡献。然而，与其他建筑材料相比，缺乏充分的研究和完善的抗震设计规定，导致钢筋砌体的使用稳步下降。部分灌浆砌体的抗震性能对于美国许多易受低概率但高后果地震事件影响的地区来说至关重要。该研究将产生具有经济竞争力的设计细节和改造方法，以提高这些结构的抗震性能和安全性。该研究将为三所参与大学的研究生和本科生提供独特的教育体验和培训。 K-12 教育部分将开发一个演示模块，将数学和科学与增强建筑环境安全的技术联系起来。该项目将利用一个由来自代码开发机构、行业和专业实践的成员组成的顾问小组。该项目的研究结果和建议将传达给相关抗震设计规范委员会，以便及时实施，从而实现更安全、抗震的砌体建筑。 该奖项是国家地震减灾计划（NEHRP）的一部分。