Numerical Analysis for Behavior of Stainless-Steel Web Cleat Connections at Elevated Temperatures

Stainless steel offers the advantages of excellent mechanical properties and exceptional corrosion resistance, making it a commonly used material in engineering. However, occasional fire incidents in engineering pose a significant risk to the safety of stainless steel structures. Among the critical components, the stainless steel beam-to-column connections play a crucial role in maintaining the structural integrity of stainless steel frames. Neglecting the influence of temperature on these connections could lead to catastrophic accidents in engineering. Thus, the main purpose of this study is to observe the behavior of stainless steel web cleat connections (SSWCC) at elevated temperatures. A finite element method, which has been validated through prior experiments, is developed to predict the behavior of the SSWCC under shear at elevated temperatures. The influences of various parameters, such as the number of bolts, angle thickness, gage distance, and temperature, on the moment-rotation behavior of the SSWCC are discussed. Temperature significantly affects both the initial rigidity and moment capacity of the SSWCC. Specifically, the initial rigidity and moment capacity of specimens decrease by 75% and 85%, respectively, when the temperature increases from 300°C to 900°C. Previous models do not precisely match the moment-rotation curves of the SSWCC at elevated temperatures; consequently, more precise model for the initial rigidity of the SSWCC at elevated temperatures are proposed in this work. Additionally, a previous model based on the yield line method is improved to represent the moment capacity of a SSWCC more accurately.