SGER: Critical Appraisal of Research Needs for SMF Connections in Steel Buildings

SGER：钢结构建筑中 SMF 连接研究需求的严格评估

• 批准号: 0335718
• 负责人: Linda Hanagan
• 金额: $ 2.03万
• 依托单位: Pennsylvania State Univ University Park
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-09-01 至 2004-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0335718&HistoricalAwards=false
• 关键词: SGER; Critical; Appraisal; Research; Needs

SGER: Critical Appraisal of Research Needs for SMF Connections in Steel Buildings; CMS proposal 0335718 PI: Linda Hanagan, Penn State UniversityFollowing the 1994 Northridge earthquake, unexpected damage was discovered in steel moment connections. To address this substantial safety issue, the Federal Emergency Management Agency (FEMA) funded the SAC Joint Venture, which produced the FEMA 350-series guideline documents, state of the art reports and other publications. Subsequently, theses findings have been incorporated into the building code requirements for new buildings. Since the publication of these guideline documents, the American Institute of Steel Construction (AISC) has formalized as requirements many of the recommendations made for steel building design and construction through the ongoing development of the consensus standard Seismic Provisions for Structural Steel Buildings (AISC, 2002). In this way, work is ongoing to incorporate the lessons learned from the Northridge earthquake into the building code requirements for new buildings.Because the FEMA 350-series documents are not consensus standards, the recommendations contained therein must undergo an adoption process. Presently, the Seismic Provisions for Structural Steel Buildings (AISC, 2002) define the beam-to-column connection requirements for classification as a special moment frame. The essence of these requirements is to provide not only adequate strength, but also adequate ductility. Conformance with this requirement can be satisfied in one of two ways: by testing or by using a connection "prequalified" in accordance with Appendix P of the Seismic Provisions. To alleviate the need for project based testing, AISC, through its Connections Prequalification Review Panel (CPRP), is in the process of developing a consensus standard. This standard is expected to be modeled after FEMA 350 in that it will outline design, detailing, and fabrication procedures for several connections that are considered prequalified without further testing. The premise is that adequate testing and evaluation has been conducted for a range of typical connections such that they can be included in the consensus standard. In fact, the hope was that the recommendations of FEMA 350 could be adopted in their entirety with some minor modification. Since the publication of FEMA 350, many of the recommendations contained therein have been brought into question by the Structural Engineers Association of California (SEAOC) and others. With the exception of RBS connection, every other connection (WUF-W, FF, WFP, BFP) have received an unfavorable rating in the SEAOC Commentary. The CPRP will seriously consider the concerns raised by SEAOC and others. Currently, task groups within the CPRP are reviewing the FEMA 350 recommendations and the supporting data for conformance with prequalification requirements set forth in the Seismic Provisions (AISC 2002). Without immediate investigation into some of the critical concerns, it is very possible that the first edition of the prequalified connections standard, which will effectively govern all steel moment frame construction in seismic areas, will contain only the RBS connection. After so many resources were dedicated to this topic, this would be a very unfortunate and unnecessary result for the building industry.PROPOSED RESEARCHBecause most of the SAC Joint Venture research was done in parallel, the research on individual connections did not have the benefit of retrospective analysis. With some exploratory funding the PI's role as a CPRP member can be extended to accomplish three additional objectives: 1) Review existing literature and test data for the possibility of extrapolating connection specific results to other connections. Accomplishing this objective may have the result of more connections being included in the AISC connection prequalification standard. 2) Develop a set of current research needs as identified through the work of the CPRP and the PI. As one of the members of the CPRP, the PI is in a somewhat unique position to identify research required to expand the AISC standard to include more of the FEMA 350 recommended connections. 3) Formulate a research proposal, to be submitted under the NEES Consortium program, to address some of the critical research needs identified under goal #2. SGER JUSTIFICATIONThis research can be characterized as having "severe urgency" in that accomplishing the objectives is dependant on the deliberations of the CPRP, which have already begun. It is expected that the work conducted under the proposed research initiative will have a nearly immediate impact on the development of the AISC prequalification standard. Without the tangential focus afforded by the proposed research, it is possible that much of the work on conections other than the RBS will be rendered useless by the CPRP until further investigation is conducted.

SGER：钢结构建筑中SMF连接研究需求的关键评估; CMS提案0335718 PI：琳达哈纳根，宾夕法尼亚州立大学1994年北岭地震后，在钢弯矩连接中发现了意想不到的损坏。为了解决这一重大安全问题，联邦应急管理局（FEMA）资助了SAC合资公司，该公司编制了FEMA 350系列指南文件、最新技术报告和其他出版物。随后，这些调查结果已被纳入新建筑物的建筑规范要求。自这些指导性文件发布以来，美国钢结构协会（AISC）已通过持续发展的共识标准《钢结构建筑抗震规定》（AISC，2002），将钢结构建筑设计和施工的许多建议正式确定为要求。因此，正在努力将北岭地震的经验教训纳入新建筑的建筑规范要求，因为FEMA 350系列文件不是共识标准，其中所载的建议必须经过采纳过程。目前，《钢结构建筑抗震规定》（AISC，2002）将梁柱连接要求定义为特殊弯矩框架。这些要求的本质是不仅要提供足够的强度，而且要提供足够的延展性。符合这一要求可以通过以下两种方式之一来满足：通过测试或使用符合抗震规定附录P的“预先合格”的连接。为了减轻对基于项目的测试的需求，AISC通过其连接资格预审审查小组（CPRP）正在制定一个共识标准。本标准预计将仿照FEMA 350，因为它将概述几个连接的设计、详图和制造程序，这些连接被认为是预先合格的，无需进一步测试。前提是对一系列典型连接进行了充分的测试和评估，以便将其纳入共识标准。事实上，希望FEMA 350的建议可以在稍作修改后全部通过。 自FEMA 350出版以来，其中包含的许多建议已被加州结构工程师协会（SEAOC）和其他机构提出质疑。除RBS连接外，所有其他连接（WUF-W，FF，WFP，BFP）在SEAOC评论中都获得了不利的评级。CPRP将认真考虑SEAOC和其他人提出的关切。目前，CPRP内的任务组正在审查FEMA 350建议和支持数据，以符合抗震规定（AISC 2002）中规定的资格预审要求。如果不立即调查一些关键问题，很有可能第一版的合格连接标准将只包含RBS连接，该标准将有效地管理地震区的所有钢框架结构。在投入了这么多资源之后，这对建筑业来说将是一个非常不幸和不必要的结果。建议的研究由于SAC合资企业的研究大多是并行进行的，因此对单个连接的研究没有回顾性分析的好处。通过一些探索性资金，PI作为CPRP成员的角色可以扩展到实现三个额外的目标：1）审查现有文献和测试数据，以确定将连接特定结果外推到其他连接的可能性。实现这一目标可能会导致更多的连接被纳入AISC连接资格预审标准。2)制定一套通过CPRP和PI的工作确定的当前研究需求。作为CPRP的成员之一，PI在确定扩展AISC标准以包括更多FEMA 350推荐连接所需的研究方面处于某种独特的地位。3)制定一项研究提案，根据NEES联盟计划提交，以解决目标#2下确定的一些关键研究需求。这项研究可以被描述为具有“严重的紧迫性”，因为实现目标取决于CPRP的审议，而CPRP已经开始。预计在拟议的研究计划下开展的工作将对AISC资格预审标准的制定产生几乎立即的影响。如果没有所提出的研究所提供的切向焦点，在进行进一步的调查之前，CPRP可能会使RBS以外的许多关于连接的工作变得毫无用处。