This paper investigated experimentally the progressive collapse risk of three one-third scale single story, two-bay steel frames under column-loss event. Progressive collapse was simulated by applying a vertical loading on the middle column. In these tests, three different types of steel beam-to-column connections were studied. These included: one shear-connection specimen that signified the prevalent type of steel beam-column joints, and two different steel intermediate moment frame (IMF) connections conforming to ANSI/AISC 358–16. The three tested specimens along with another two 2D steel frames with IMF connection, tested in the literature, were used to calibrate 3D finite element (FE) models prepared using ABAQUS software. The validated FE models were then employed to investigate the risk of progressive collapse for eleven different types of steel IMF beam-column joints under middle column-loss scenario. Out of the eleven specimens, eight connections were designed as per ANSI/AISC 358–16; two joints were in accordance with EN 1993-Eurocode 3 and the last connection was in conformance with the 2007 Turkish-Earthquake Code (TEC-2007). Performance of different IMF connections was compared based on their modes of failure and load-displacement response in both flexural and catenary action stages.

本文通过实验研究了在柱损失事件下三个三分之一比例的单层两居室钢框架的逐步倒塌风险。通过在中间列上施加垂直荷载来模拟渐进倒塌。在这些测试中，研究了三种不同类型的钢梁到柱连接。其中包括：一个剪切连接样本，表示钢梁-柱节点的普遍类型，以及两个不同的符合ANSI / AISC 358-16的钢中间矩框架（IMF）连接。在文献中测试的三个测试样本以及另外两个带有IMF连接的2D钢框架，用于校准使用ABAQUS软件准备的3D有限元（FE）模型。然后，使用经过验证的有限元模型来研究在中柱损失情况下11种不同类型的IMF钢制梁柱节点逐渐坍塌的风险。在11个样本中，按照ANSI / AISC 358-16设计了8个连接；两个接头符合EN 1993-Eurocode 3，最后一个接头符合2007年土耳其地震法规（TEC-2007）。根据不同的IMF连接在弯曲和悬链作用阶段的失效模式和载荷-位移响应的性能进行了比较。两个接头符合EN 1993-Eurocode 3，最后一个接头符合2007年土耳其地震法规（TEC-2007）。根据不同的IMF连接在弯曲和悬链作用阶段的失效模式和载荷-位移响应的性能进行了比较。两个接头符合EN 1993-Eurocode 3，最后一个接头符合2007年土耳其地震法规（TEC-2007）。根据不同的IMF连接在弯曲和悬链作用阶段的失效模式和载荷-位移响应的性能进行了比较。