Anti-Progressive Collapse Performance of Fully Bolted Steel Frame Structure Connections Based on Performance Improvement

This paper presents a study on the performance of two types of fully bolted connections in relation to progressive collapse. Two specimens were specifically designed and fabricated to represent these connections. One specimen utilized the traditional double web angle connection (DWA), while the other employed a new type of connector, resulting in a new fully bolted connection (NFB). The study thoroughly investigated various aspects of the specimens, including failure modes, load–displacement responses, and resistance mechanisms. The findings revealed that the flexural behavior and ultimate behavior of the NFB connection were superior to those of the DWA connection, particularly in terms of flexural behavior. However, the rotational behavior of the NFB connection was slightly inferior to that of the DWA connection. Additionally, refined numerical models were used to simulate the failure modes and load–displacement responses of both connections, and a strong correlation was observed between the test results and the numerical analysis. Furthermore, a parametric analysis of the NFB connection was conducted, leading to the discovery that modifying the structural type of the new connector, specifically adjusting the form of part C from flush to extended, was the most effective measure for enhancing the anti-progressive collapse capacity of the NFB connection. Moreover, the rotational capacity and ultimate load-carrying capacity of the NFB connection could be improved by adjusting the thickness of the new connector and increasing the diameter of the bolts within the steel beam.