Evaluation of Reinforced Steel Moment Connections

钢筋弯矩连接的评估

• 批准号: 9416287
• 负责人: Michael Engelhardt
• 金额: $ 7万
• 依托单位: University of Texas at Austin
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1994
• 资助国家: 美国
• 起止时间: 1994-09-01 至 1996-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9416287&HistoricalAwards=false
• 关键词: Evaluation; Reinforced; Steel; Moment; Connections

9416287 Engelhardt The January 1994 Northridge Earthquake caused unprecedented damage at beam-to-column connections in steel moment resisting frames. The failures occurred largely at the standard welded flange - bolted web type of steel moment connection. These failures reflected nonductile behavior, and has raised serious questions on current methods and standards of design. The research undertaken in this project will experimentally evaluate the performance of reinforced moment connections. Two reinforcing schemes will be investigated. Both involve the addition of reinforcing plates at the connection. The reinforcing plates substantially increase the flexural capacity of the connection, and at the same time, reduce stress levels on the beam flange welds. The lower weld stresses will significantly reduce the sensitivity of the connection to welding quality. Such reinforced connection details have shown promising performance in limited past tests. However additional large scale verification of these details is needed, and will be provided by this research project. Most tests will be conducted using beam steels with high yield strength and high yield to tensile strength ratio, in order to provide a severe test of the reinforced connections. However, some tests will also be conducted using beam steels with a controlled low value of yield and yield to tensile strengths. These tests will demonstrate the role of steel strength characteristics in the observed connection failures, and investigate the possibility of improved connection performance through control of steel material properties. The results of this testing program will provide urgently needed data for structural engineers and building code officials involved with design of new steel moment frames, as well as the repair or retrofit of existing steel moment frames. This is a Northridge Earthquake project. ***

9416287 Engelhardt 1994年1月，诺斯里奇地震在防止钢板上的固定镜架上造成了前所未有的损坏。 故障大部分发生在标准焊接法兰 - 螺栓网络类型的钢矩连接。 这些失败反映了非统治行为，并就当前的设计方法和标准提出了严重的问题。 该项目进行的研究将在实验中评估增强力矩连接的性能。 将研究两个加强计划。 两者都涉及在连接处添加加固板。 加固板显着增加了连接的弯曲能力，同时降低了梁法兰焊缝上的应力水平。 较低的焊接应力将显着降低连接对焊接质量的敏感性。 这种加强的连接细节在过去的测试有限的情况下显示出了有希望的表现。 但是，需要对这些详细信息进行大规模验证，并将由该研究项目提供。 大多数测试将使用具有高屈服强度和高产与拉伸强度比的梁钢进行，以便对增强连接进行严格的测试。 但是，还将使用具有控制的低收率和收率的抗拉力强度的梁钢进行了一些测试。 这些测试将证明钢强度特征在观察到的连接故障中的作用，并通过控制钢材材料特性来改善连接性能的可能性。 该测试计划的结果将为结构工程师和建筑法规官员提供急需的数据，以及与新的钢矩框架设计以及现有钢矩框架的维修或改造。 这是一个诺斯里奇地震项目。 ***