*Review* **An Overview of Progressive Collapse Behavior of Steel Beam-to-Column Connections**

#### **Iman Faridmehr <sup>1</sup> and Mohammad Hajmohammadian Baghban 2, \***


Received: 19 July 2020; Accepted: 27 August 2020; Published: 29 August 2020

**Abstract:** Local failure of one or more components due to abnormal loading can induce the progressive collapse of a building structure. In this study, by the aid of available full-scale test results on double-span systems subjected to the middle column loss scenario, an extensive parametric study was performed to investigate the effects of different design parameters on progressive collapse performance of beam-to-column connections, i.e., beam span-to-depth ratio, catenary mechanism, and connection robustness. The selected full-scale double-span assemblies consisted of fully rigid (welded flange-welded web, SidePlate), semi-rigid (flush end-plate, extended end-plate), and flexible connections (top and seat angle, web cleat). The test results, including load-deformation responses, development of the catenary mechanism, and connection robustness, are presented in detail. The finding of this research further enables a comprehensive comparison between different types of steel beam-to-column connections since the effects of span-to-depth ratio and beam sections were filtered out.

**Keywords:** progressive collapse; steel beam-to-column connections; catenary mechanism; double-span assemblies; stiffness degradation
