Collaborative Research: Dynamic Disproportionate Collapse in Flat-Plate Buildings

这项合作研究的目的是为大型住宅和办公综合体中常用的旧钢筋混凝土平板建筑的不成比例倒塌分析提供急需的实验数据和有效的建模方法。将进行试验和分析研究，以检查这种平板结构在极端荷载事件期间突然失去柱子的情况下的性能。试验将在静力和动力荷载作用下的横向约束板柱节点和突然释放荷载的多板试件上进行。这些试验将提供数据，以确定分析建模所需的关键参数，确定平板体系的局部强度和变形能力，并研究板柱节点的冲压后性能。有限元模拟将用于促进试验设计、确定局部变形需求、确定故障传播特征以及检验试验中未考虑的其他设计参数的影响。还将开发简化的分析工具，以便在不进行详细的有限元分析的情况下，快速评估平板建筑的渐进倒塌弹性。该项目的研究将改进在极端荷载事件下更安全的平板建筑的设计指南。从这项研究中获得的数据还将有助于为易发生不成比例倒塌的平板结构制定适当的修复方法。研究成果将通过出版物、演示文稿和为该项目创建的网站向结构工程界传播。高中生和本科生将参与这个项目，以提高他们对工程的研究兴趣。研究成果将纳入与楼板结构相关的研究生水平课程，该项目将通过参与项目研究活动为研究生提供高级培训。

The goal of this collaborative research is to provide much needed experimental data and effective modeling approaches for the disproportionate collapse analysis of older reinforced concrete flat-plate buildings that are commonly used for large residential and office complexes. Experimental and analytical studies will be conducted to examine the performance of such flat-plate structures under the scenario of a sudden loss of a column during an extreme loading event. The experiments will be performed on laterally restrained slab-column connections under static and dynamic loading and multi-panel specimens subjected to sudden load release. The tests will be conducted to provide data to define key parameters needed for analytical modeling, to identify the local strength and deformation capacity of the flat-plate systems, and to study the post-punching behavior of slab-column connections. Finite element simulations will be employed to facilitate the design of experiments, to determine local deformation demands, to define failure propagation characteristics, and to examine the effects of other design parameters not considered in the experiments. Simplified analytical tools will also be developed for quick evaluation of the progressive collapse resilience of flat-plate buildings without conducting a detailed finite element analysis. The research in this project will lead to improved design guidelines for safer flat-plate buildings under extreme loading events. The data obtained from this study will also help in the development of appropriate rehabilitation approaches for flat-plate structures that are vulnerable to disproportionate collapse. Research findings will be disseminated to the structural engineering community through publications, presentations, and websites created for this project. High school students and undergraduate students will be engaged in this project to enhance their research interests in engineering. Research results will be integrated into the graduate level courses related to slab structures, and the project will provide advanced training to graduate student through their involvement in the project research activities.