SGER: Progressive Collapse Investigation of an Existing Steel Frame Building

这个小型探索性研究补助金(SGER)项目的主要研究目标是：1)审查和评估当前的逐步倒塌设计标准和指南；2)按照现行规范的规定对现有的钢框架建筑进行建模和分析；3)通过移除三到四根一层柱进行试验，并调查建筑物随后的倒塌或损坏进度。可以进行倒塌测试的实际建筑非常有限，因此必须抓住这个机会。位于俄亥俄州立大学校园的一座四层钢框架建筑将被建模和分析，以调查其对连续倒塌的脆弱性。根据现行设计准则和规范标准的建议，将切割和移除一个角柱和几个一层周长柱，并将随后的结构反应与计算机模拟预测的结构反应进行比较。许多研究人员已经进行了分析研究，以评估现行逐步倒塌设计指南的有效性和一致性。然而，为了验证这些分析研究的结果和验证准则中规定的方法，开展的实验研究非常有限。这主要是因为建造和测试全尺寸建筑试件通常很困难，而且这种大规模测试的费用高得令人沮丧。作为实验研究的一部分，将有可能测试一座计划拆除的真实四层建筑。试验数据将有助于调查现行指南的有效性和有效性，并提供可用于验证倒塌模拟的实际倒塌行为。研究将对新的设计和抗倒塌建筑结构的修复和加固产生重大影响。该研究成果除可为实际建筑拆除某些承重构件或柱后的试验性能提供必要的信息外，还可用于预测类似平面布置的钢结构的抗倒塌性能。这一实验和分析研究计划的结果可能会影响目前为建筑物逐步倒塌评估和设计制定的实践和指南。从测试建筑观察到的倒塌失败模式将提供当前指南的保守性程度的指示。作为分析调查的一部分，测试结果将与模拟的预测响应进行比较。由于实际建筑物的倒塌实验数据非常有限或没有，因此研究结果将对结构工程界产生广泛影响，包括研究人员和从业者。目前简化的分析程序的有效性将使用测试结果进行验证。这也将为参与实验的本科生和研究生提供特殊的体验。

The main research objectives of this Small Grant for Exploratory Research (SGER) project are to: 1) review and evaluate the current progressive collapse design criteria and guidelines, 2) model and analyze an existing steel frame building following the current code provisions, and 3) conduct an experiment by removing three or four first-story columns and investigate the subsequent collapse or damage progress in the building. The availability of actual buildings that can be tested to collapse is very limited, so it is imperative that this opportunity be taken. A four-story steel frame building located on the Ohio State University campus will be modeled and analyzed to investigate its vulnerability against progressive collapse. As recommended by the current design guidelines and code standards, one corner column and several first-story perimeter columns will be cut and removed, and the ensuing structural response will be compared with that predicted from the computer simulation. Many researchers have conducted analytical studies to evaluate the effectiveness and consistency of the current progressive collapse design guidelines. However, very limited experimental research was performed to validate the results of those analytical studies and to verify the methodologies prescribed in the guidelines. This is mainly because it is usually difficult to construct and test full-scale building specimens and such large-scale testing is discouragingly expensive. As part of the experimental research, it will be possible to test a real four-story building scheduled for demolition. The test data will enable investigation of validity and effectiveness of the current guidelines and provide actual collapse behavior that can be used to validate collapse simulation.The research will have significant impact, specifically on the new design and repair and strengthening of collapse-resistant building structures. In addition to providing much needed information on the experimental behavior of a real building after the removal certain load carrying elements or columns, the research results could be used to predict the collapse resistance of similar steel buildings with regular floor plans. The results from this experimental and analytical research program are likely to impact the current practice and guidelines developed for progressive collapse evaluation and design of buildings. The observed collapse failure mode from the test building will provide an indication of level of conservativeness of the current guidelines. Test results will be compared with the predicted response from simulations as part of the analytical investigation. Since there is very limited or no experimental collapse data from real buildings, the outcome of the research will have broad impacts on the structural engineering community, including researchers and practitioners. The validity of the current simplified analysis procedures will be verified using the test results. This will also provide an exceptional experience for undergraduate and graduate students who will be involved in the experiments.