Gravity Load Capacity of Earthquake Damaged Slab-Column Connections

地震受损板柱连接的重力承载能力

• 批准号: 0301632
• 负责人: James Jirsa
• 金额: $ 27.65万
• 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: 2003
• 资助国家: 美国
• 起止时间: 2003-08-01 至 2006-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0301632&HistoricalAwards=false
• 关键词: Gravity; Load; Capacity; Earthquake; Damaged

PI: James Jirsa, UT-Austin.The objective of this project is the determination of critical shear, moment, and deformation interactions for reinforced concrete slab-column buildings. Flat plate and flat slab floor systems are widely used in residential and commercial buildings with low gravity loads. Two-way or punching shear capacity of flat plate and flat slab floors is quite low. Shear strength calculations for such connections are complex and involve interaction between moment and shear transfer. Shear capacity is adversely affected by inelastic action that occurs at the connection. Deformation or drift must be controlled to limit damage. The poor performance of buildings in the 1985 Mexico City and other earthquakes since then has demonstrated the weaknesses in these structures. Little is known about the effect of inelastic deformations due to lateral displacements of the structure on subsequent shear transfer capacity under gravity loadings. The keystone of the research program is experimental testing to determine the relationship between punching shear capacity of the slab-column connection under gravity loads and the level of previous damage to the slab by earthquake (or other severe loading such as blast, wind, or settlement) actions on the structure. The information will be valuable for the following uses: 1. Determining the conditions under which punching shear failures due to gravity loads will occur after the structure has suffered earthquake damage by determining the degree of damage through visual observations, measured local or global deformations, or with non-destructive techniques. 2. Developing response characteristics for slab-column connections for use in pushover or other seismic analyses of new or existing structures. 3. Establishing reasonable deformation limits for evaluation and design of rehabilitation schemes for existing slab-column structures. 4. Evaluating the feasibility of strengthening slab-column connections. The project will create knowledge in an area that is new to the profession and essential to understanding the performance of structures during and after an earthquake. There is very little experimental evidence available to guide the research and design community in evaluating and rehabilitating systems where damage during an earthquake (or other severe loadings such as blast, wind, or settlement) can have deleterious impact on the subsequent behavior of the structure under different load combinations. The PI will make data available to the NEES network. Results will be disseminated through reports made available to the earthquake engineering community, articles in technical journals, and presentations at technical conferences. Practicing engineers will be involved in the development of the project details. Special efforts will be made to secure students from the graduate and undergraduate student bodies in the UT, CE program that has large fractions of women and Hispanic students. The findings from the research will be utilized immediately in a graduate course on evaluation and rehabilitation of existing reinforced concrete structures. The PI will use existing University programs, and direct contacts with local high school science teachers, to encourage a high-school student to choose engineering as a career.

主要研究者：本项目的目标是确定钢筋混凝土板柱建筑物的临界剪力、弯矩和变形相互作用。平板和无梁楼盖系统广泛应用于低重力荷载的住宅和商业建筑中。 平板和无梁楼盖的双向或冲切承载力较低。这种连接的抗剪强度计算是复杂的，涉及力矩和剪力传递之间的相互作用。抗剪承载力受到连接处发生的非弹性作用的不利影响。必须控制变形或漂移以限制损坏。 在1985年墨西哥城地震和此后的其他地震中，建筑物的性能很差，这表明了这些结构的弱点。由于结构的侧向位移引起的非弹性变形对重力荷载下的剪切传递能力的影响知之甚少。 研究的重点是试验测试，以确定板柱连接在重力荷载作用下的冲切承载力与地震（或其他严重荷载，如爆炸、风或沉降）对结构的作用对板的先前损坏程度之间的关系。这些信息将是有价值的以下用途：1。 通过目视观察、测量局部或整体变形或使用非破坏性技术确定损坏程度，确定结构遭受地震损坏后，由于重力荷载而发生冲切破坏的条件。2. 开发板柱连接的响应特性，用于新结构或现有结构的推覆或其他地震分析。3. 为既有板柱结构加固方案的评估和设计确定合理的变形限值。4. 板柱节点加固的可行性评估。 该项目将在一个新的专业领域创造知识，这对理解地震期间和之后的结构性能至关重要。很少有实验证据可用于指导研究和设计界评估和修复地震（或其他严重荷载，如爆炸、风或沉降）期间的损坏可能对不同荷载组合下结构的后续行为产生有害影响的系统。 PI将向NEES网络提供数据。研究结果将通过向地震工程界提供的报告、技术期刊上的文章以及技术会议上的演讲进行传播。 执业工程师将参与项目细节的制定。 将作出特别努力，以确保学生从研究生和本科学生团体在UT，CE计划，有很大比例的妇女和西班牙裔学生。 研究结果将立即用于现有钢筋混凝土结构评估和修复的研究生课程。PI将利用现有的大学课程，并与当地高中科学教师直接联系，鼓励高中生选择工程作为职业。