SGER: Large-Scale Validation of Seismic Performance of Bridge Columns

SGER：桥梁柱抗震性能的大规模验证

• 批准号: 0738014
• 负责人: Stephen Mahin
• 金额: --
• 依托单位: University of California-Berkeley
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2007
• 资助国家: 美国
• 起止时间: 2007-09-01 至 2010-02-28
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0738014&HistoricalAwards=false
• 关键词: SGER; Large; Scale; Validation; Seismic

The goals of this Small Grant for Exploratory Research (SGER) project are to: (1) provide the nucleus around which other investigators, practitioners, and funding agencies can participate; (2) actively collaborate in the planning of the E-Defense bridge column test program; (3) compile and distribute (in accordance with NEES Consortium, Inc., and E-Defense policies) data from the entire test series, including archival in the NEES data repository; (4) conduct a series of experiments on full-scale bridge columns detailed consistent with current U.S. design practices; (5) interpret these data in terms of other data from the E-Defense test program, as well as from previous reduced-scale tests in the United States; (6) carry out numerical simulations using advanced physics-based models as well as simpler phenomenological models of the type used in design practice; (7) evaluate current design and analysis practices in view of these tests and analyses; and (8) widely disseminate results.Major transportation structures, such as bridges, have suffered tremendous damage in recent earthquakes, as observed during the 1989 Loma Prieta, 1994 Northridge, 1995 Hyogo-Ken Nanbu, Japan, and 2001 Nisqually earthquakes. Such damage limits the ability of the affected community to conduct emergency response operations, slows recovery, and strains the limited resources available for post-event reconstruction and development. Many have conjectured that such damage could have been avoided had large-scale seismic tests been done on bridges prior to these earthquakes. Fortunately, considerable experimental data has become available during the past two decades to help improve design, evaluation, and retrofit methods based on quasi-static, pseudo-dynamic and dynamic tests of bridge components. However, these dynamic tests of bridge columns have all been conducted using substantially reduced (one-tenth to one-quarter) scale specimens. Because many important modes of behavior (shear, anchorage, and fracture) do not reproduce well in reduced scale models, the earthquake engineering community has placed high priority on carrying out realistic, full-scale shaking table tests of bridge columns. The recent construction of the Earth Defense (E-Defense) shake table at the Hyogo Earthquake Engineering Research Center in Miki, Japan makes such experiments now feasible. Japanese researchers are moving ahead rapidly to conduct research on full-scale bridge columns and systems using the E-Defense facility. During 2007 and 2008, they will use E-Defense to conduct a series of experiments on approximately seven full-scale reinforced concrete bridge columns representative of past and current Japanese design and construction practices. While these tests will provide fundamental data on the dynamic behavior of full-scale columns, the usefulness of this data by itself to the U.S. engineering community is not optimal.This project responds to an exceptional immediate opportunity for U.S. researchers, practitioners, and students to participate in the planning, conduct, analysis and interpretation of these experiments. Planning in Japan is well advanced, and significant resources are being mobilized to carry out the tests. The strong U.S. collaboration already established with the Japanese team of investigators makes this project feasible. This investigation will obtain, interpret and disseminate the first shake table results for full-scale bridge columns. Comparison of results for the U.S. and Japanese specimens with past tests and with analytical simulations will provide a critically needed assessment of the adequacy of reduced-scale models and tests conducted at altered strain rates. Comparison of U.S. and Japanese design practices in light of observed performance will provide new insights into bridge behavior. It will provide missing data needed to increase confidence in analysis methods and validate (or improve) current design methods. This research is of high priority nationally to federal and state bridge agencies and industry.The impact of the project will be broadened by the planned dissemination of results and by the substantial anticipated exchange of faculty members, students, professionals, and others.

这个探索性研究（SGER）项目的目标是：（1）提供其他研究人员，从业者和资助机构可以参与的核心;（2）积极合作规划电子防御桥柱测试计划;（3）编译和分发（根据NEES联盟，Inc.，和电子防御政策）整个测试系列的数据，包括NEES数据存储库中的档案;（4）对详细与当前美国设计实践一致的全尺寸桥柱进行一系列实验;（5）根据电子防御测试计划以及美国之前的缩小规模测试的其他数据解释这些数据;（6）使用先进的基于物理的模型以及设计实践中使用的简单的现象学模型进行数值模拟;（7）根据这些测试和分析评估当前的设计和分析实践;（8）广泛传播研究结果。主要的交通结构，如桥梁，在最近的地震中遭受了巨大的破坏，正如1989年洛马普列塔地震中所观察到的那样，1994年北岭地震、1995年兵库县南部地震和2001年尼斯夸利地震。这种破坏限制了受灾社区开展应急行动的能力，减缓了恢复速度，并使可用于灾后重建和发展的有限资源捉襟见肘。 许多人认为，如果在地震发生前对桥梁进行大规模的地震测试，这种破坏是可以避免的。幸运的是，在过去的二十年中，大量的实验数据已经成为可用的，以帮助改善设计，评估和改造方法的基础上准静态，伪动态和动态测试的桥梁组件。然而，这些桥柱的动态测试都是使用大幅减少（十分之一到四分之一）规模的标本。由于许多重要的行为模式（剪切、锚固和断裂）在缩尺模型中不能很好地再现，地震工程界高度重视对桥柱进行真实的、全尺寸的振动台试验。 最近在日本三木的兵库地震工程研究中心建造的地球防御（E-Defense）振动台使这样的实验现在变得可行。日本研究人员正在迅速推进使用电子防御设施对全尺寸桥梁支柱和系统进行研究。在2007年和2008年期间，他们将使用E-Defense对大约7个代表日本过去和现在设计和施工实践的全尺寸钢筋混凝土桥梁柱进行一系列实验。虽然这些测试将提供有关全尺寸柱的动态行为的基本数据，但这些数据本身对美国工程界的有用性并不是最佳的。该项目为美国研究人员、从业人员和学生提供了一个特殊的直接机会，可以参与这些实验的规划、实施、分析和解释。 日本的规划工作进展顺利，正在调动大量资源进行试验。美国已经与日本调查小组建立了强有力的合作关系，这使得该项目可行。这项调查将获得、解释和传播全尺寸桥柱的第一个振动台结果。将美国和日本试样的结果与过去的试验和分析模拟进行比较，将提供一个急需的评估，以评估在改变应变率下进行的缩尺模型和试验的充分性。根据观察到的性能比较美国和日本的设计实践将为桥梁行为提供新的见解。它将提供所需的缺失数据，以增加分析方法的置信度，并验证（或改进）当前的设计方法。 这项研究是高度优先国家联邦和州桥梁机构和行业。该项目的影响将扩大的计划传播的结果，并通过大量预期的教师，学生，专业人员和其他人的交流。